Abstracts from the World Conference on Interventional Oncology (WCIO) 2016

ABSTRACTS FROM WCIO

World Conference on Interventional Oncology (WCIO) 2016 June 9-12, 2016, Boston, Massachusetts

W. Yang1, F. Yan2, S. Wang1, J. Fu1, K. Yan1, H. Zheng2, M. Chen1. 1 Ultrasound, Peking University Cancer Hospital, Beijing, China; 2 Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China. Objective: To investigate the role of a tumor-penetrating peptide integrated thermo-sensitive liposomal doxorubicin in the drugs accumulation of liver tumors and animal end-point survival. Methods: Approval from the Institutional Animal Care and Use Committee was obtained before the study. First, characterization of the iRGD-LTSL was performed in vitro study. Second, temperature-dependent release profile of DOX from iRGD-LTSL and cell toxicity was tested in H22 cell. Next, H22 liver adenocarcinomas were implanted in 156 mice in in vivo study. Tumors were randomized into six groups (n=8 each group): (a) no treatment; (b) iRDG-LSTL (doxorubicin 1mg/kg); (c) LSTL alone; (d) RF alone (70°C, 5mins); (e) RF ablation followed LSTL by at 30 min (LSTL+RF), (f) RF ablation followed by iRDG-LSTL (iRDG-LSTL+RF). The distribution and accumulation were compared for different groups (n=6) at 2, 24, and 48 hrs after treatment. Kaplan-Meier analysis was used to compare end-point survival (30 mm diameter). Additionally, the body weight change during long-term follow up (90 days) was analyzed. Results: In vitro, the DOX encapsulation efficiency in iRGD-LTSL was approximately 97.5 %. Temperature-dependent drug release capability was confirmed by keeping iRGD-LTSL solutions at 42°C for 2-min each hour. In H22 cell experiment, the cell uptake ratio for iRGD-LTSLs quantitatively was about 6.07-fold or 1.25-fold higher than that for LTSLs, respectively at 1, 2 hours. In vivo, there was significantly increased intratumoral DOX accumulation in iRGD-LTSL+RF at 2 hr (684r105 vs. 556r98 ng/g, P=0.013), compared with LTSL +RF group. For end-point survival, the iRDGLSTL+RF group (mean, 36.7r20.5 days) had a better survival result than LSTL+RF (27.4r2.9 days, P=0.001), RF alone (21.3r2.8 days, P=0.002), iRDG-LSTL(21.0r2.1 days, P=0.001) or LSTL alone (21.2r2.0 days, P<0.001). During follow up, we found no obvious changes in the body weight after treatment in the 5 experimental groups. Conclusions: Conjugation to iRGD significantly improved the specificity of tumor-accumulation and enhanced the activity of thermo-sensitive liposomal Doxorubicin without increasing the side reaction.

Methods: Firstly, we observed the morphological characterization of Matrigel at different temperatures in vitro. Secondly, we conducted in vivo study using 42 SD rats in Matrigel, D5W and control groups of 14 rats each. Artificial ascites with 10ml of Matrigel or D5W was produced under ultrasound guidance before RF in the experimental groups. Using a 0.7 cm exposed 17G RF electrode for 5 minutes (90r2°C), we performed 41 hepatic ablations abutting the diaphragm, abdominal wall and stomach. The 41 rats were sacrificed at 24 hours, and necropsy was performed. We performed gross and histopathologic examinations to compare the frequency and extent of thermal injury to the nearby organs. Finally, we followed up the animal status to achieve long term safety evaluation of Matrigel. Results: Firstly, Matrigel was in liquid formation at 0-4°C,but was not moving in vials at temperature 37°C in 1 minute, presenting gel formation. Secondly, in vivo experiment, the artificial fluid thickness of Matrigel in site was significantly larger than that of the D5W group, especially at 5 minutes of ablation (8.1r1.1 mm vs 2.4r0.8 mm, P<0.001). Thermal injury to the nearby structures was found in 12 of 13 (92.3%) cases in the control group, 8 of 14 cases (57.1%,P=0.037) in the D5W group, and 1 of 14 cases (7.1%, P<0.001) in the Matrigel group. The sizes of the ablation zone of the liver did not differ among the three groups. There was no difference in the incidence of operation related complications among the three groups. Finally, there was no significant difference in body weight and health related parameters between the Matrigel and D5W group during 60 days of follow up. Conclusions: Using thermo-sensitive Matrigel as artificial ascites may be a safe and useful technique and help to further reduce the frequency and severity of collateral thermal injury to the nearby structures compared to conventional D5W, during RF ablation of subcapsular hepatic tumors.

Paper 2: Effect of Artificial Ascites with Thermo-Sensitive Matrigel on Minimization of Thermal Injury to the Nearby Structures in Radiofrequency Ablation of Subcapsular Hepatic Tumors in a Rat Model J. Fu, W. Yang, S. Wang, K. Yan, M. Chen. Ultrasound, Peking University Cancer Hospital, Beijing, China.

Paper 3: MRI and 3D-Biopsy-Based Treatment of Prostate Cancer with Irreversible Electroporation (IRE)

Objective: To evaluate the effect and safety of using thermo-sensitive Matrigel as artificial ascites on minimizing thermal injury to the nearby structures in a rat model of radiofrequency (RF) ablation of the liver.

M.K. Stehling1, N. Klein1, E. Guenther1, S. Zapf1, B. Rubinsky2. 1 Radiology, Institut fuer bildgebende Diagnostik - Prostata Center, Offenbach am Main, Germany; 2Department of Mechanical Engineering, University of California Berkeley, Berkeley, CA.

All WCIO abstracts and posters are graded via blinded peer review based on scientific merit, originality, relevance and clarity. SIR assumes no legal liability or responsibility for the completeness, accuracy, and correctness of the information presented in the abstracts. Abstracts will be published in the Journal of Vascular and Interventional Radiology as submitted by the authors, except for minor stylistic adjustments to ensure consistency of format and adherence to abstracts style. Additional WCIO and CIO abstracts are available online at www.jvir.org. ©SIR, 2016 J Vasc Interv Radiol 2016; 27:e47–e114 DOl: 10.1016/j.jvir.2016.04.006

Objective: Irreversible Electroporation (IRE) is gaining significant recognition as an effective alternative for the treatment of various cancers, including prostate cancer (PCa). It specifically impairs and destroys cells, potentially sparing sensitive tissue structures such as the neurovascular bundle, sphincter or rectum, making it applicable to patients at all stages of the disease (T1-T4) and patients with recurrent disease. However, as a minimally invasive image guided therapy, the treatment success is primarily determined by treatment planning. We further discuss the performance of multiparametric (mp)-MR imaging of the prostate with additional transperineal 3D biopsy for optimal treatment planning for IRE therapy of PCa. Methods: In the course of four and a half years, 265 patients with various stages of PCa (T1-T4) or recurrent PCa were treated with IRE under ultra-sound guidance. Treatment planning was based on mp-MRI in all cases (T2, diffusion, perfusion, and in selected cases 1H spectroscopy) with use of an endorectal coil. In 116 cases, additional transperineal 3D-biopsy was performed and taken into account for treatment

WCIO Abstracts

Paper 1: A Tumor-Penetrating Peptide Integrated Thermo-Sensitive Liposomal Doxorubicin Enhances the Efficacy of Drugs Accumulation and Animal Survival

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planning. Follow-up MRI was done one day after IRE as well as 3, 6 and 12 months after IRE, if possible. After one year, most patients did yearly follow-ups. Results: Initial tumor ablation was successful in all cases. Thirteen patients with Gleason 7 or higher had recurrent disease within the follow-up time of up to four and a half years, while no recurrent PCa occurred for patients with Gleason 6. Eight patients with recurrent PCa did not undergo transperineal 3D-biopsy, while in 7 cases the recurrent was outside the treatment field. Twenty-seven patients reported a transient reduction of erectile function (recurred after 6-8 months), while 15 have noted a persistent reduction. No severe IRE-related adverse events took place, while most adverse events which occurred (total: 51) were related to catheterization (transient urinary retention, dysuria, urinary tract infection). Four medically significant adverse events occurred (self-healed recto-prostatic fistula, self-healed bladder perforation, necessity for TURP). No patient suffered from incontinence after the treatment. Conclusions: IRE treatment of prostate cancer is safe and can be seen an effective tumor ablation modality in consideration of the follow-up time of four and a half years. IRE is suitable not only for the treatment of PCa of early stages, but also recurrences after any kind of previous treatments, and for advanced T3 and T4 cancers which are not amenable to surgery or radiation therapy anymore. Treatment planning based on the combination of mp-MRI and 3D-biopsy showed high efficacy for all stages of the disease, while MRI is suitable for post-treatment follow-up. IRE of the prostate has the potential to become the new standard of care in the treatment of PCa. Paper 4: An Economic Analysis of Percutaneous Ablation Versus Surgery for Small Renal Cancers in the Medicare Population A.D. Talenfeld1, C.L. Atoria2, E.B. Elkine2, M.C. Brunner3, S.W. Kwan4. 1 Radiology, Weill Cornell Medicine, New York, NY; 2Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY; 3 Radiology, Madison VAH, University of Wisconsin Madison School of Medicine, Madison, WI; 4Radiology, University of Washington Medical Center, Seattle, WA. Objective: Percutaneous thermal ablation (PA) is a minimally-invasive, nephron-sparing alternative to partial nephrectomy (PN) or radical nephrectomy (RN) for some patients with small renal cancers. Our objective was to compare costs associated with each procedure through the first year after treatment in a population-based cohort of older adults. Methods: In the linked Surveillance, Epidemiology and End Results-Medicare dataset we identified patients age 66 or older who received PA, RN or PN within 6 months of diagnosis of a clinically-staged T1a renal cancer in 2006-2011. Cost was defined as the amount reimbursed by Medicare on all inpatient, outpatient, physician, durable medical equipment, home health, and hospice claims. We analyzed treatment costs and cumulative costs at 30 days, 90 days, and 365 days after treatment. Inpatient treatment costs were considered to be comprised of all reimbursements from index admissions plus carrier claims for the day of treatment. Outpatient treatment costs were defined as all claims on the day of treatment. Cumulative 365-day costs were defined as all payments made by Medicare in the 365-day period beginning with the day of treatment. All costs were inflated to 2012 dollars. Pre-existing conditions were identified in Medicare claims in the year prior to cancer diagnosis. Multivariable log-linear regression was used to estimate associations between treatment approach and costs, controlling for demographic and health characteristics. Results: There were 460, 1,626 and 2,336 patients treated with PA, PN and RN, respectively. Median treatment costs were $4,265, $14,412 and $14,710 for PA, PN and RN, respectively. Median cumulative costs at 365 days post-procedure were $12,590, $21,702 and $23,063. Controlling for demographic and disease characteristics, both treatment costs and one-year costs were significantly lower for patients treated with PA compared to either PN or RN (P<0.0001). Cost increased with increasing patient age. Controlling for treatment and baseline characteristics, one year costs were significantly higher in patients with greater Charlson comorbidity scores and those with diabetes at baseline (P<0.05)(P<0.05). Both treatment costs and one-year costs were greater in patients with baseline renal insufficiency or cardiovascular disease (P<0.001). Treatment costs decreased from 2006 through 2011 for all procedure types. Conclusions: From the payer perspective, PA for older patients with T1a renal cancer is associated with significantly lower costs than PN or RN both at the time of treatment and through the first year after treatment. In well-selected patients with small tumors, PA may be a less costly alternative to surgery.

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Paper 5: Split-Bolus Single-Phase Contrast-Enhanced Cone-Beam CT (CBCT) for Detection of Hypervascularized Liver Lesions and Feeding Arteries M. Jonczyk1, J. Chapiro1, F. Collettini1, D. Geisel1, D. Schnapauff1, F. Streitparth1, T. Schmidt2, B. Hamm1, G. Wieners1, B. Gebauer1. 1 Department of Radiology, Charité University Medicine Berlin, Berlin, Germany; 2Healthcare, Philips GmbH Market DACH, Hamburg, Germany. Objective: The purpose of this study was to evaluate the hypervascularization and the visibility of feeding arteries of primary and secondary liver lesions in an intraindividual comparison between a peri-procedural CBCT using a split-bolus, single-phase contrast injection protocol and a pre-procedural contrast-enhanced MRI. Methods: This IRB-approved, prospective study included 13 patients with liver lesions (N=11 HCC, N=1 esophageal carcinoma, N=1 Ewing sarcoma). All patients had a contrast-enhanced MRI examination (using Primovist, Bayer, Germany) within one month before TACE. CBCT images were acquired using XperCT roll protocol on Allura FD20 (Philips, The Netherlands) using a single-phase, split-bolus contrast injection (8ml at 1.5ml/s followed by a 15s [HCC]/25s [non-HCC] delay and 18ml at 1.5ml/s using Imeron 300 [Bracco Imaging, Germany], in a 50% solution, injected with an Accutron HP-D-HT injector [Medtron, Germany]), through catheters placed in the proper hepatic artery. An intraindividual lesion-by-lesion comparison with previously acquired arterial phase MRI was performed to evaluate the modality-specific detectability. Lesion’s hypervascularisation was evaluated using a 5 point scoring system (I: no visibility, II: poor differentiation, III: acceptable contrast, IV: good differentiation, V: excellent visibility). Visibility of feeding arteries was categorized in a 3 point scoring system (I: no visibility, II: poor delineation, III: good visibility). Statistical analysis included the non-parametric Wilcoxon matched-pairs test. A P-value <0.05 was considered as significant. Results: A total of 38 lesions were evaluated. On CBCT, hypervascularization of 9 lesions were classified as type V and 17 lesions were regarded as score IV. N=11 hypervascularizations detected by CBCT were not visible on corresponding MR imaging. N=1 hypervscularized lesion identified on MRI was not detected on CBCT. Statistical analysis revealed a better visualization of hypervascularization in CBCT compared to MRI (P=0.003). Feeding arteries of 2 lesions could not certainly be detected on CBCT, whereas 4 feeding arteries were classified type II and 31 as type III with good visibility. However, MRI depicted 7 lesions with a good visibility (III) of the feeding arteries and 6 class II feeders. MRI failed to depict feeding arteries for 25 lesions. Vasculare supply was therefore better delineated on CBCT than on MRI (P<0.001). One target lesion was not detected on CBCT as it was located outside of the field of view. Conclusions: A single-phase, split-bolus injection CBCT protocol can be used for delineation of the hypervascularization of primary and secondary hepatic tumors and their feeding arteries before intervention. The improved diagnostic ability of the proposed CBCT protocol can be used for secure planning of TACE procedures. Paper 6: Clinical Outcomes of Percutaneous Microwave Ablation for Hepatocellular Carcinoma with a Minimum of 1-Year Follow-Up P.F. Laeseke, T. Ziemlewicz, M. Lubner, J.L. Hinshaw, S.A. Wells, F. Lee. Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI. Objective: Early safety and efficacy data on microwave ablation for hepatocellular carcinoma (HCC) is available in the literature. However, studies with longer term follow-up and outcome data are lacking. The purpose of this study is to report clinical and oncologic outcomes of patients with HCC treated using microwave ablation at a single tertiary care center who have a minimum of 1-year follow-up. Methods: Between January 2011 and October 2014, 94 BCLC stage A patients with 141 treatment-naive HCCs were treated in 106 sessions of percutaneous microwave ablation utilizing US and CT guidance. There were 76 male and 18 female patients with mean age of 61.0 years (range 44-82). All procedures were performed with a single microwave system that employs 1-3 internally gas cooled antennas (mean 1.6 antennas/tumor). Mean total ablation time was 5.2 minutes (range 1-12.5 minutes). Results: Mean tumor diameter was 2.1 cm (range 1.0 to 4.2 cm) and median follow-up was 22 months (range 12-57 months). Technical success was achieved in 99.3% (140/141) of tumors in a single session. Overall primary treatment effectiveness was 92.1% (130/141). Primary treatment effectiveness was 91.9% (114/124) for tumors < 3 cm, 100% (15/15) for tumors 3-4 cm, and 50% (1/2) for tumors > 4 cm. Distant intrahepatic progression occurred in 23.4% of patients during follow-up. There was a single major complication (0.9%), a pneumothorax requiring placement of a pleural blood patch, and no procedure related mortality. Median local progression-free survival was 21 months.

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Conclusions: Local tumor control rates for HCC treated with microwave ablation are higher than those reported for HCC treated with other modalities. Consideration should be given to adding microwave ablation to guidelines for the treatment of HCC. Paper 7: Radiologic/Pathologic Correlation of Explanted Hepatocellular Carcinoma Following Drug-Eluting Bead Chemoembolization A. Milisavljevic, A. Ahmad, I. Feurer, A. Lipnik, F. Banovac, D. Brown, S. Geevarghese, S. Salaria. Vanderbilt University School of Medicine, Nashville, TN.

Correlation of Radiologic/Pathologic Correlation by Quintiles

produce significant stratification between responders and non-responders, or did not generate any separation at all (Table1, Figure 1). qEASL was the only criterion to generate significant stratification with p=0.046 and p=0.015 for combination therapy and control groups, respectively. Inter-reader agreement was 0.984 for qEASL. Conclusions: qEASL shows promise in predicting survival for HCC treated with combination therapy, and is a better survival predictor than 1- and 2-dimensional response assessment methods. Target Lesion Response.

WCIO Abstracts

Objective: Imaging changes estimate outcomes following intra-arterial therapy for hepatocellular carcinoma (HCC). Explant pathology is definitive, with previous studies evaluating radiologic/pathologic outcomes of conventional trans-arterial chemoembolization (TACE) and Y90. Our aim was to determine the concordance between radiologic and pathologic assessment of HCC response after treatment with drug-eluting bead (DEB) TACE. Methods: We reviewed 25 patients (20 male, mean age 62 r 6 years, range 53-73) with 32 HCC lesions who underwent imaging and liver transplantation after DEB-TACE. Percent necrosis and imaging response were evaluated using modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria and correlated with percent necrosis at explant using the Edmondson criteria. Outcomes were reported by lesion. Data were analyzed using nonparametric correlation coefficients, median, and Wilcoxon signed rank tests. Results: The mean difference in percent necrosis (explant minus imaging) was -1.6 ± 10.9% and these measures were highly correlated (rho=0.933, P<0.001). Quintiles for percent necrosis via imaging and pathology are described in the table. Among the 32 tumors, ordinal mRECIST classes were 3 progressive disease, 9 stable, 10 partial, and 10 complete response, which correlated with percent necrosis on explant (rho=0.766, P<0.001). At explant, 7 tumors were well-, 14 moderately-, and 3 poorly-differentiated. The remaining tumors were necrotic with no residual tumor. Necrosis ranged from 0-90%, 0-100% and 15-90% in the well, moderately and poorly differentiated tumors, respectively. Differentiation did not correlate with necrosis (P=0.386). Conclusions: Imaging estimations of necrosis following DEB-TACE correlate closely with necrosis on explant pathology. Patients with the most notable responses on imaging also have the greatest necrosis on explant. Tumor differentiation is not a predictor of necrosis after DEB-TACE.

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Univariate analysis with Cox model of responders and non-responders according to RECIST, WHO, mRECIST, EASL, vRECIST, and qEASL guidelines. R=responder; NR=nonresponder; NM=not measurable

Paper 8: 3D Quantitative Response Assessment after Combination Therapy of Conventional TACE (cTACE) and Bevacizumab in Patients with HCC W. Manzano2, S. Smolka1, J. Treilhard3, E. Reiner4, S. Kabus5, J. Chapiro1, J. Duncan3, M. Lin6, J. Geschwind4. 1Charite University Hospital Berlin, Berlin, Germany; 2School of Medicine, University of California, Irvine, Irvine, CA; 3Yale School of Engineering, New Haven, CT; 4Radiology, Yale School of Medicine, New Haven, CT; 5Philips Research, Hamburg, Germany; 6Philips Research North America, Cambridge, MA. Objective: To determine whether 3D tumor enhancement (quantitative EASL [qEASL]), compared with other criteria (RECIST, mRECIST, WHO, EASL, vRECIST), can better assess tumor response and predict survival for HCC after combination therapy of cTACE and bevacizumab. Methods: In a single-center retrospective study, we evaluated 14 patients with HCC treated with cTACE and bevacizumab in a Phase II clinical trial from 2006-2008. A control group of 28 patients was created by manually matching in a 1:2 ratio with patients of the same Child-Pugh, BCLC, and HKLC stage, but treated with cTACE only. The largest target lesion was segmented in 3D on baseline and follow-up MR imaging. Pre-contrast and arterial-phase T1 sequences were registered and then subtracted; the difference was used for quantitative 3D analysis using qEASL (Philips Healthcare, Haifa, Israel). qEASL response was defined as t65% decrease in volumetric tumor enhancement. The same target lesion was measured using RECIST, mRECIST, WHO, EASL, and vRECIST. All measurements were conducted by 2 independent readers and averaged. Kaplan-Meier and Cox proportional model were employed. Results: Median overall survival (OS) was 10.3r12.7 months for combination therapy patients, and 14.7r2.5 months for patients who received TACE only. No significant difference existed between qEASL’s ability to predict survival after combination therapy versus TACE only (P=0.716). In both combination therapy and control groups, RECIST, mRECIST, WHO, EASL, and vRECIST either did not

Kaplan-Meier curves showing survival of responders(R) versus non-responders (NR) as measured by response criteria for the combination therapy group. Paper 9: Combined Transarterial (Chemo)embolization and CT-Guided High-Dose-Rate Brachytherapy in Patients with Unresectable Hepatocellular Carcinoma B.R. Tegel, M.J. Powerski, P. Podrabsky, B. Gebauer, D. Schnapauff. Radiology, Charité Berlin, Berlin, Germany. Objective: The treatment of patients with unresectable Hepatocellular Carcinoma remains challenging and reported median survival according to the Barcelona Clinic Staging System (BCLC) is limited, with reported median survival of 20 months for BCLC B and 11 months for BCLC C. The aim of this study is to evaluate the outcome of patients undergoing a combined therapy consisting of embolization followed by CT-guided High-Dose-Rate Brachytherapy (CT-HDRBT). Methods: We retrospectively reviewed the clinical course of 47 consecutive patients with unresectable HCC who have been treated at the Charité Berlin,

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Department of Radiology between March 2011 and March 2015. The treatment took place in two different groups: The first group received transarterial chemoembolisation (TACE) before CT-HDRBT while the second group was treated with bland transarterial embolisation (TAE) before CT-HDRBT. Follow-up was performed using contrast-enhanced MRI (Gd-EOB-DTPA, Primovist®, Bayer, Germany) at 6 weeks initially followed by 3 months intervals. Primary endpoint was the overall survival (OS), secondary endpoints were the local time to progression (local TTP) and the Time To Progression (TTP). Results: Totally, 78 HCC lesions with a median diameter of 35,5 mm (7-144 mm, mean 41,2 mm) were treated. 12 Patients presented with portal vein invasion, liver function complied with Child-Pugh stage A in 39 patients and with Child-Pugh B in 6 patients. 4 patients were classified as BCLC A, 30 patients as BCLC B and 13 patients as BCLC C. Median follow-up time was 17,8 months (1,7-49,5 months, mean 20,7 months).20 patients died during the follow-up period and 2 patients had liver transplantation and were therefore excluded from survival analysis. Median OS was 19,1 months (1,7-49,5 months, mean 21,2 months). 7 patients developed a local recurrence in the ablated area (local progression rate 9%), median LTP was 16,4 months (1,7-49,5 months, mean 19,0 months). Median TTP was 9,3 months (1,3-49,5 months, mean 13,0 months). The comparison of the two groups TACE+CT-HDRBT and TAE+CT-HDRBT showed no statistically significant difference in OS (mean: 28,3/33,1 months, P=0,492), lTTP (mean: 39,4/38,0 months, P=0,360) or TTP (mean 18,1/19,8 months, P=0,924). Stratified to BCLC stage patients with BCLC stage A disease had a mean OS of 31,6 months (11,4-41,7 months). BCLC B patients had a median OS of 30,1 months (1,7-49,5 months, mean 31,2 months) while stage C patients still had a median OS of 17,7 months (2,8-44,9 months, mean 28,2 months). Conclusions: The combination of embolization and CT-HDRBT showed very good results in local tumor control as well as in the OS in our cohort of patients with large tumors, who are typically out of range for local tumor ablation. Especially in patients with advanced stage HCC the observed OS was considerably better. Compared to bland embolization, chemoembolization did not show any superiority, rejecting at the current point the idea of a radiosensitization for subsequent brachytherapy. As retrospective trial without control arm of standard therapy this study has limitations and results should be confirmed by a prospective randomized trial. Paper 10: A Novel Tri-Modal Gold Nanocomplex for Image-Guided Thermal Ablation of Liver Tumors 1

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A.K. Parchur , J.M. Jagtap , G. Sharma , V. Gogineni , M. Flister , S.B. White1, A. Joshi1. 1Radiology, Medical Colege of Wisconsin, Milwaukee, WI; 2Physiology, Medical College of Wisconsin, Milwaukee, WI. Objective: Au nanoparticle (NP) mediated plasmonic thermal ablation is limited by the challenges of specific delivery to tumors and lack of options for real-time guidance via clinically available imaging modalities. We report a novel 70 nm NP comprising of an Au nanorod core for plasmonic ablation/X-ray contrast, and shell of NdF3/GdF3 for stable optical luminescence and T1-MR contrast. We demonstrate the feasibility of DynaCT and optical image guided Au NP site specific delivery and thermal ablation of colorectal liver metastasis (CRLM) in a rat model. Methods: PEGylated Au@NdF3@GdF3 core/shell NPs were synthesized using schematic diagram shown in Fig. 1A and NPs were concentrated to 1013 NPs/mL. The emission spectral verification and NIR imaging was performed with NIRvana:640ST InGaAs shortwave IR camera equipped with SP-2156 spectrograph (Princeton Instruments). An 808 nm (Pmax = 200 mW) diode laser (Thorlabs) was used as an excitation source and a 808 nm notch filter and 950 nm long-pass filters employed for optical imaging. Three rats (500 g), one having no tumor and other two with CRLM tumor were selected for the experiment. NPs (~500 PL) were directly injected through mesenteric vein into the liver and ~180 Pm fiber-optic laser probe was inserted for the PTT ablation. PTT ablation was performed for 3 min after NPs injection using a 808 nm (4 W) laser. A clinical Dyna CT operated at 66 and 81 kV was used to track the uptake of the NPs into the liver. Results: Core/shell NPs (~70 nm) demonstrated three NIR emission peaks at 900, 1064, and 1300 nm on excitation with 808 nm laser irradiation. NIR imaging was performed pre- and post- therapy to track the NPs delivery to tumor. Fig.1C and D illustrate the pre and post thermal therapy luminescence image depicting nanoparticle distribution in liver. The bio-distribution of NPs and effect of PTT ablation was studied using dual-energy DynaCT imaging (Fig.1B). 81 kV DynaCT enabled NP visualization in the rats injected with nanocomplexes, the contrast was increased and localized in the PTT+NPs treated rat. Control rat (PTT without NP) didn’t exhibit CT contrast in the treated region. The nanoparticles had strong T1 MR contrast, which was not employed in this study, but can be used a pre-procedure planning tool. Conclusions: In summary, we have successfully prepared Au@NdF 3@GdF3 core/shell NPs as an NIR triggered and targeted theranostic platform for the trimodal image guided PTT for CRLM tumor bearing rats. Current and future studies will focus on in vivo studies with statistically significant animal group size and longitudinal tracking of therapy efficacy.

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Figure 1. (a) Schematic illustration of the synthesis of core/shell NPs synthesis, (b) Dyna CT image of PTT performed on control rat with no tumor and NPs (PTTonly), tumor rat with NPs and no PTT (NPs only), and tumor rat with NPs and PTT (NPs+PTT), and (c) NIR imaging of tumor rat at pre- and post- therapy. Paper 11: Response Assessment in Patients with Infiltrative and Multifocal Hepatocellular Carcinoma after Transarterial Chemoembolization by Volumetric Enhancement Quantification of the Whole Liver on Multiphasic MRI: A Preliminary Study S. Smolka1, C. Liu2, T. Schlachter7, J. Treilhard15, R. Schernthaner3, J. Chapiro9, S. Sahu8, J. Ho Sohn14, Y. Zhao4, F.N. Fleckenstein6, M. Lin10, R. Ardon5, R. Duran11, B. Gebauer12, J. Geschwind13. 1Charite University Hospital Berlin, Berlin, Germany; 2radialogy and biomedical imaging, yale university, New Haven, CT; 3Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; 4Interventional Radiology, Johns Hopkins Hosptial, Baltimore, MD; 5Medisys, Philips Research, Suresnes, France; 6Interventional Radiology, Johns Hopkins Hospital, Baltimore, MD; 7Yale School of Medicine, New Haven, CT; 8 Johns Hopkins Hospital, Baltimore, MD; 9Charite University Hospital, Berlin, Germany; 10Philips Research North America, Cambridge, MA; 11 Johns Hopkins Hospital, Baltimore, MD; 12Charite University Hospital, Berlin, Germany; 13Yale School of Medicine, New Haven, CT; 14Johns Hopkins Hospital, Baltimore, MD; 15Yale School of Engineering, New Haven, CT. Objective: The ill-defined borders in infiltrative hepatocellular carcinoma (HCC) and the sheer number of lesions in multifocal HCC can pose a challenge in response assessment after Transarterial Chemoembolization (TACE) with traditional methods (i.e. RECIST, mRECIST, WHO, EASL). Our preliminary study investigates the feasibility of whole liver volumetric enhancement quantification to measure treatment response and predict survival. Methods: From 2000 to 2014, 68 HCC patients with infiltrative or multifocal growth were retrospectively included and underwent MRI before and 1 month after their first TACE. For each session separately the whole liver was segmented and pre-contrast and arterial phase T1 sequences were subtracted. Viable tumor was identified in voxels enhancing above 2 times the standard deviation of enhancement inside a region of interest (ROI) placed in non-tumorous liver parenchyma, as previous work has shown to correlate with pathology. Hyperenhancing volume was noted in percent relative to the whole liver volume and compared to overall survival (OS). Kaplan–Meier analysis with log-rank test and Cox regression were performed. A threshold at 35% reduction between baseline and follow-up MRI was used to separate responders from non-responders. Results: Mean age was 63.3 years, 77.9% of patients were male and 64.7% had portal venous invasion. 33.8% of patients showed infiltrative growth pattern only, 33.8% infiltrative with solid parts and 32.4% multifocal HCC (>20 lesions). There was a statistically significant difference between responders and non-responders

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(p=0.011). The hazard ratio of death for responders was 0.336 (95%CI 0.139-0.810). Responders (14.7% of the patients) had an OS of 21.0r7.0 months, whereas non-responders (85.3%) had an OS of 6.8r1.4 months. Responders had a mean 57.8% decrease in enhancing volume, whereas non-responders on average had a 19.1% increase. Conclusions: Our preliminary findings indicate that whole liver volumetric enhancement quantification on MRI can be used as an imaging biomarker for tumor response and survival in infiltrative and multifocal HCC that evades standard assessment methods.

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Multiphasic baseline MR (top row) and follow-up MR (bottom row) with arterial phase image, 3 D visualization of the whole liver mask and the quantification based on the subtracted image. Placement of cubic ROI in non-tumorous liver tissue. Enhancement quantification shows successful chemoembolization by marked reduction of hyper enhancing liver tissue. Paper 12: Pain Palliation and Radiographic Local Control of Spinal Metastases with Combination Radiofrequency Ablation, Vertebral Augmentation, and Radiation Therapy A.N. Wallace1, T.J. Greenwood1, T. Madaelil2, J.W. Jennings2. 1 Neuroradiology, Mallinckrodt Institute of Radiology, Creve Coeur, MO; 2 Mallinckrodt Institute of Radiology, Saint Louis, MO. Objective: To evaluate the efficacy of combination radiofrequency ablation (RFA), vertebral augmentation (VA), and radiation therapy (RT) in terms of pain palliation and radiographic local tumor control in patients with metastatic spine disease. Methods: Medical records of all patients who underwent combination RFA, VA, and RT of spinal metastases between April 2012 and May 2015 were reviewed. Lesion characteristics were assessed on pre-procedure imaging. Pre- and post-procedure mean worst pain scores 1- and 4-weeks after treatment were measured using the Numeric Rating Scale (10-point scale) and compared. Post-treatment imaging was reviewed for radiographic evidence of tumor progression. Clinical outcomes and duration of follow-up were also recorded. Results: During the study period, 75 spinal metastases in 48 patients were treated with RFA, VA, and RT. Eighty nine percent (67/75) of metastases involved the posterior vertebral body, 29% (22/75) eroded through the posterior vertebral body cortex, and 61% (46/75) involved the pedicles. The median pre-procedure pain score was 8.0. Clinically significant decreased median pain scores of 5.0 (P<0.0001) and 3.0 (P<0.0001) were reported at 1- and 4-week follow-up, respectively. Post-treatment imaging of 68 tumors (91%; 68/75) was assessed for evidence of radiographic tumor progression. Of these, radiographic local tumor control rates were 83% (40/48) at 3 months, 78% (36/44) at 6 months, and 71% (20/28) at 1 year after treatment. Median clinical follow-up was 28 weeks (interquartile range, 15 - 44 weeks), during which no complications were reported and no patients suffered clinical evidence of metastatic spinal cord compression at the treated level(s). Conclusions: Combination RFA, VA, and RT appears to be a safe and effective treatment for pain palliation and local control of spinal metastases.

34-year-old man with Ewing sarcoma and mid back pain. Axial (A) and sagittal (B) T2-weighted MRI show hyperintense metastasis in the posterior T7 vertebral body (black asterisk) that extends into the left pedicle and erodes into the epidural space (black arrow). The T7 metastasis was treated with radiofrequency ablation and vertebral augmentation followed by radiation therapy to T6-T10 (2,000 cGy, 5 fractions). His back was resolved at 1- and 4-week follow-up. Axial (C) and sagittal (D) MRI obtained 8 weeks after percutaneous treatment shows signal void in the vertebral body corresponding to cement (white asterisk), the ablation probe track traversing the left pedicle (white arrow), and retraction of previously seen epidural tumor. Paper 13: The Effects on Stasis of D5W versus H2O to Infuse Y90 Resin Microspheres M. Koran1, S. Stewart1, A. Lipnik2, R.A. Omary3, F. Banovac4, D. Brown1. 1 Vanderbilt University, Nashville, TN; 2Vanderbilt University, Nashville, TN; 3Vanderbilt University, Nashville, TN; 4Vanderbilt University, Nashville, TN. Objective: Manufacturer recommendations for resin Y90 microsphere infusion has traditionally utilized sterile water (H2O). In the summer of 2013, recommendations expanded to allow infusion of 5% dextrose in water (D5W). We reviewed our initial experience with D5W and compared microsphere delivery and incidence of stasis to a historic control using H2O, testing the hypothesis that D5W administration allows for higher Y90 dosage delivery rates with lower stasis incidents. Methods: IRB waiver of consent was obtained. From 9/2013-7/2014, 62 infusions using resin Y90 were performed using H2O or D5W and compared to an existing trial with data from 128 infusions using only H2O. Y90 dosimetry for all infusions

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was calculated using the body surface area method with dose reduction allowed for patients who had been pretreated with multiple rounds of chemo or intra-arterial therapy. Infusion was halted if intra-arterial stasis was identified fluoroscopically prior to clearing the vial as the final infusion step. No anti-reflux devices were used. Differences from the cases using H2O and D5W were calculated for activity prescription, percentage of cases reaching stasis, and percentage of prescribed activity using z- and t-test comparisons. Results: Of the total of 190 infusions, 137 used H2O and 53 used D5W. There was a significant difference in the proportion of stasis between the H2O and D5W groups, where there was decreased stasis in the D5W cases, from 23% stasis rates in the H2O group to 4% stasis rates in the D5W group (z= 3.07, p=1.05E-3). The D5W group also had a significantly higher dose prescribed than the H2O cohort (28.2 mCi and 20.4 mCi, respectively; t=5.0, p=1.1E-6). In addition, the D5W cohort had a higher percentage of the delivery of the prescribed dose than the H2O cases (101.5% and 92.7%, respectively; t=3.8, p=1.92E-4). Conclusions: We found that cases utilizing D5W had significantly lower rates of stasis, even with a higher dose of Y90 delivered, supporting our initial hypothesis. Institutions administering Y90 should institute this methodology of D5W delivery to increase technically successful Y90 procedures. Paper 14: Survival Analysis of 8000 Cases of Cancer Treated by Percutaneous Cryosurgery L. Niu. Guangzhou FuDa Cancer Hospital, Guang zhou, China. Objective: To evaluate the role of cryosurgery in patients with solid tumors with systemic immunotherapy. Methods: We systematically reviewed 8000 cancer patients, about 70% from overseas, who received comprehensive cryotherapy in our hospital between October 2003 to October 2013. During the past 10 years, comprehensive cryotherapy (including ablation of the primary and metastatic lesions) has been used to significantly reduce tumor load, cryo-immunotherapy has been used to improve physical fitness and prevent tumor recurrence. Results: Our retrospectively analyzed the inclusion patients and found that: for patients with metastatic breast cancer, the median survival after cryotherapy was 55 months, the survival time of patients after cryo-immunotherapy can reach to 83 months; for patients with metastatic non-small cell lung cancer, the median survival after cryotherapy was 14 months, the median survival of patients after cryo-chemo-immunotherapy was 27 months; for central-type lung cancer, the progress-free survival (PFS) of endotracheal type tumor was 8 months, PFS of tracheal wall or extratracheal type were 13 or 14 months; for patients with metastatic hepatocellular cancer, the median survival after cryotherapy was 26 months, the median survival of patients after cryo-immunotherapy can reach to 32 months; for patients with metastatic pancreatic cancer, the median survival after cryotherapy was 8 months, median survival of patients after cryo-immunotherapy can reach to 13 months. Conclusions: Cryo-immunotherapy can further enlarge the survival time of patients with solid tumors. Paper 15: Preventing Cardiac Complications during Percutaneous Microwave Lung Ablation Near the Heart: Effect of Antenna Position on Risk of Cardiac Tissue Injury and Significant Arrhythmia in a Swine Model G. Carberry5, E. Nocerino2, P. Mason4, D. Schwahn6, S. Hetzel3, A. Turnquist1, C. Brace7, F. Lee5. 1University of Wisconsin--Madison, Madison, WI; 2radiology, università degli studi di milano, Milan, Italy; 3Biostatistics, University of Wisconsin, Madison, WI; 4Division of Cardiovascular Medicine, University of Wisconsin, Madison, WI; 5 Radiology, University of Wisconsin, Madison, WI; 6Comparative Pathology, University of Wisconsin, Madison, WI; 7Biomedical Engineering, University of Wisconsin, Madison, WI. Objective: To determine the shortest distance between the antenna and heart at which a percutaneous pulmonary microwave (MW) ablation can be safely performed. Methods: Fluoroscopic computed tomography (CT)-guided MW ablation of the lung was performed in 11 swine under general anesthesia and mechanical ventilation. Ablations were performed with a single 17-gauge gas-cooled antenna which was randomized to either a perpendicular (90 +/- 20 degrees) or parallel (180 +/- 20 degrees) orientation with respect to the surface of the heart. Distance between the antenna and the heart was randomized to 0.75 mm increments between 0 mm and 10 mm, with the final antenna distance measured during cardiac diastole with the use of continuous CT fluoroscopy. Continuous electrocardiography (ECG) was monitored and recorded during the ablations. The ablations were performed for 5 minutes at 65 W unless a significant arrhythmia (defined as asystole, heart block, bradycardia, supraventricular or ventricular tachycardia) developed. After the ablations, swine were euthanized and tissue changes assessed with vital stain and histology. ECG rhythms were retrospectively interpreted by a cardiologist. The risk of cardiac tissue injury and significant arrhythmia as a function of distance and

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orientation relative to the heart was evaluated by mixed effects logistic regression. Receiver operating characteristic (ROC) curves were generated to determine safe ablation cut-off distances at each antenna orientation. Results: Thirty-four MW ablations were performed in the lung with the antenna located < 10 mm from the heart (range: 0 to 9.9 mm). Seventeen ablations (50%) were performed in the perpendicular orientation and 17 (50%) in the parallel orientation. Significant arrhythmias developed during 6 (18%) ablations at an average of 69 (+/- 22 seconds) into the ablation. Cardiac tissue injury occurred in 17 ablations (50%). Risk of arrhythmia and cardiac tissue injury decreased with increasing antenna distance from heart in both antenna orientations. No significant arrhythmia or tissue injury occurred with a distance t 4.4 mm and t 4 mm from the heart in the parallel and perpendicular antenna orientations, respectively. Areas under the ROC curves for significant arrhythmia or tissue injury with a distance of < 4.2 mm in the parallel orientation and < 3.5 mm in the perpendicular orientation, are 1 (95% CI: 1.000, 1.000) and 0.965 (95% CI: 0.893, 1.000), respectively. Conclusions: The risk of cardiac tissue injury or significant arrhythmia during percutaneous microwave ablation in the lung can be minimized by positioning the antenna at least 5 mm from the heart. Paper 16: Effect of Vessel Diameter on Frequency of Pulmonary Artery Branch Occlusion during Central Microwave Pulmonary Ablation in a Swine Model G. Carberry2, E. Nocerino1, F. Lee2, C. Brace3. 1Radiology, Università Degli Studi di Milano, Milan, Italy; 2Radiology, University of Wisconsin, Madison, WI; 3Biomedical Engineering and Medical Physics, University of Wisconsin, Madison, WI. Objective: To determine if the risk of pulmonary artery (PA) occlusion immediately following microwave (MW) ablation in the lung is related to vessel diameter Methods: Computed tomography (CT) fluoroscopy-guided percutaneous MW pulmonary ablations were performed in 8 pigs under general anesthesia. For each ablation, a single 17-gauge gas-cooled MW antenna was positioned within lung tissue less than 1 cm from the heart to replicate central pulmonary ablations. All ablations were performed at 65 W for 5 minutes. A CT angiographic pulmonary embolism protocol scan (100 mL Iohexol 300 with 10 mL saline chase, 5 ml/sec; Smart Prep; 1.25 mm slice thickness, 0.625 interval, Smart mA, 120 kVp) was performed in each pig before and immediately after the ablations. Following euthanasia, the lungs were removed and 3-dimensional gross measurements made of the pulmonary ablation zones to corroborate CT ablation zone volumes. The CT images were retrospectively reviewed by two authors and the volume of each ablation zone, as well as the number, maximum diameter, and patency of the PA branches within each ablation zone was recorded. Student’s t-test was used to calculate statistical significance (p < 0.05). Results: Twenty-one in vivo pulmonary MW ablations were performed with no more than 3 ablations in each animal. Six of the ablation zones (29%) contained at least 1 occluded PA branch. The mean maximum diameter of the occluded PA branches in the ablation zones was 2.4 mm (range: 2 - 2.8 mm). The mean maximum diameter of the non-occluded PA branches in the ablation zones was significantly larger measuring 3.7 mm (range: 2.1 - 6.9 mm) (p = 0.009). Seven of the 21 PA branches < 3 mm in maximum diameter in the ablation zones were occluded (33.3%) whereas no PA branches t 3 mm in size were occluded. No PA occlusions remote from the ablation zone occurred. There was no significant difference in size of CT ablation zones which contained occluded versus non-occluded PA branches (p = 0.10) or which contained 1 versus multiple PA branches (p = 0.49). Conclusions: The frequency of pulmonary artery branch occlusion immediately following percutaneous MW pulmonary ablation is related to vessel diameter with no risk to vessels t 3 mm in size when using a standard pulmonary ablation protocol. Paper 17: Development of Canine Lung Tumor Model and Its Preliminary Pharmacokinetics Study of Bronchial Artery Infusion Chemotherapy by Microdialysis Technique X. An1, Z. Sun3, W. Dong2. 1Shanghai General Hospital, Shanghai, China; 2 Shanghai Changzheng Hospital, Shanghai, China; 3Zhejiang Provincial Hospital of tradition Chinese medicine, Hangzhou, China. Objective: The difference between bronchial artery infusion chemotherapy (BAI) and conventional systemic chemotherapy is the distinction of pharmacokinetics due to drug delivery way. This study is expected to explain the different action mechanisms, and to offer a reference basis for the determination of drug protocol of BAI in order to improve its efficacy in clinical practice. Microdialysis technique was adapted to sample in lung tumor model of canine transmissible venereal tumor (CTVT) accurately in vivo. Methods: Based on our preparatory work, 18 beagle dogs were treated to percutaneous CT-guided puncture in order to transmit three fresh CTVT tumor fragments (2.0mm length) into dog lungs. After dog CTVT lung tumor model method had been created successfully, microdialysis probes were performed percutaneous puncture and implanted in lung under CT. After selective catheterization of

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CT image of CTVT tumor in the lungs

Paper 18: Impact of Germline Tumor Micro-Environment Variation on Plasmonic Photothermal Ablation of Breast Cancer J.M. Jagtap1, A.K. Parchur1, G. Sharma1, V. Gogineni1, M. Flister2, S.B. White1, A. Joshi1. 1Radiology, Medical College of Wisconsin, Milwaukee, WI; 2Physiology, Medical College of Wisconsin, Milwaukee, WI. Objective: Plasmonic photothermal therapy (PTT) with near-infrared (NIR) resonant gold (Au) nanoparticles is an emerging noninvasive treatment modality for the target-specific cancer therapy. A critical factor for success of NIR ablation is the Au nanoparticle uptake in tumors. While tumor cell autonomous factors have been investigated for nanoparticle delivery, germline variation in the tumor microenvironment has not been studied in terms of its impact on nanoparticle delivery and response to thermal therapy. Herein, we report the results of microvascular differences, nanoparticle uptake, and PTT therapy efficacy in consomic xenografts models (CXM) of human triple negative breast cancer in immune compromised rat strains with germline variations affecting the systemic vasculature. Methods: Luciferase-tagged MDA-MB-231 cells were orthotopically implanted in immune compromised SS (salt-sensitive) and SS.BN3 (third chromosome substitution of brown normal:BN) CXM rats. Rats were identical in body weight and appearance, but had subtle differences in microvascular structure. Au nanorods (200 PL; 1013 NPs/mL) or NIR dye Indocyanine green (1 mL; 400 PM) were intravenously injected. Rat and xenografted tumor vasculature was characterized by dynamic NIR fluorescence imaging at 50 ms temporal resolution following bolus injection of indocyanine green (ICG). A 785 nm diode laser (75 mW) and deep cooled intensified charge-coupled device camera (PiMAX, Princeton Instruments, Trenton, New Jersey) used for imaging, and 15 W, 808 nm laser (Diomed 15 Plus) was used for PTT. PTT was performed 5 hours after tail vein injection of Au nanorods via an expanded 808 nm laser beam covering the tumor (4–5 W/cm2) for 5 minutes. Post-therapy, rats were followed via bioluminescence imaging for two weeks. Results: Pre and post-therapy (post-therapy, 7th, and 14th day) bioluminescenceimaging are illustrated in Figure 1a, b. Both groups presented with loss of luminescence consistent with tumor cell death, however MDA-MB-231 tumors in SS.BN3 strain indicated higher rate of relapse. It is may be due to less uptake of Au nanorods in the SS.BN3 tumor microenvironment, which was further confirmed by ICP-MS quantification of Au, showing up to 20% less nanoparticle uptake. ICG dynamic NIR imaging on both SS and SS.BN3 rats further confirmed the vascular microenvironment differences. As shown in Figure 1c, a higher ICG wash-out in SS as compared to SS.BN3 rat indicated increased vascular dysfunction in SS.BN3, which can stimulate increased therapy resistance by promoting hypoxia. Conclusions: Herein, we studied the effect of the tumor microenvironment variation on PTT efficacy for the first time in a novel rat models of breast cancer. Rapid non-invasive NIR fluorescence imaging verified the vascular micro-environment differences in CXM rat models. PTT results confirms that the gold nanoparticle uptake and therapy response is sensitive to the tumor microenvironment.

Figure 1. (a) Pre and (b) post-therapy bioluminescence-imaging, (c) ICG wash-in and was-out study on SS and SS.BN3 microenvironment rats. Paper 19: Development of a 4T1 Murine Breast Cancer Cryoablation Model L. Cai1, Y. Gu1, G. Srimathveeravalli1, J. Coleman2, J.C. Durack1, S.B. Solomon1, H. McArthur3, J.P. Erinjeri1. 1Interventional Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY; 2 Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY; 3 Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY.

DSA image of CTVT tumor in the lungs

Objective: Percutaneous ablation is increasingly used for local control of solid tumors including breast cancer. We developed a small animal model of 4T1 breast cancer cryoablation for preclinical research.

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bronchial artery, Carboplatin (CBP)with doses of 16.5mg/kg in 5% glucose solution was slowly infused into the target artery. In group venous same dosage of CBP were administered through small saphenous vein. Then dialysate samples were collected and determined by high performance liquid chromatography (HPLC). Data were processed with DAS2.0/3P87 software. Results: CTVT tumor formation rate of model dogs was 100%(18/18), and the largest mean diameter display 2.734r0.138cm in the 10th week. For 14 nodules larger than 2cm, there were phenomena that visible dilated bronchial artery leading to the tumor direction on DSA and CT arteriography. Area Under Curve(AUC) is the product of drug concentration in the tissue and the time. AUC value of CBP in group BAI (1660.76r339.77mgL-1min) is significantly higher than group venous (459.49r49.99mgL-1min) (P<0.05). It indicates that with the same drug dosage, CBP bioavailability rise markedly and the cytotoxicity is strengthened in BAI. Conclusions: The experiments have proved that it is ideal method to establish lung tumor model with CTVT tissue fragments inoculation by percutaneous puncture approach. Compared with intravenous administration, BAI could significantly increase the peak concentration within the tumor, prolong the local action time, increase drug bioavailability in local tumor and enhance tumor cell killing. It suggests that BAI protocol should not apply systemic chemotherapy regime indiscriminately.

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Methods: BALB/c mice (n=40) were injected in the flank with a 4T1 mammary carcinoma cell line. Once tumors reached 5-8 mm3, visually guided cryoablation with 1.7 mm PerCryo probes was performed. Freeze cycles were discontinued when ice crystals encompassed the visible tumor and thaw cycles were discontinued when ice crystals were no longer visible. Three main treatment parameters were evaluated: Single cycle @ 20% freeze rate for up to 60 seconds (Tx1, n=10); dual cycle @ 2% freeze rate up to 90 seconds (Tx2, n=10); and dual cycle @ 20% freeze rate up to 60 seconds (Tx3, n=10). A control group was not ablated (n=10). Mice were monitored for 41 days and survival rates were recorded. Post-euthanasia, tumor, lung and liver tissues were collected and processed for immunohistochemistry. Student-Newman-Keuls method and Kaplan-Meier survival curves were constructed. Results: Mice in the treatment groups survived longer (Tx1 mean 24 days, range 17-41; Tx2 mean 27 days, range 19-41; Tx3 mean 27 days, range 17-41) than control mice (mean 19 days, range 15-23). One day after ablation, local tissue damage and swelling was observed in all treatment groups, though only significantly greater than control for groups Tx1 and Tx3 (Control tumors = 307±108 mm3; Ablation zones in mm3: Tx1= 480±160 (p=0.014), Tx2= 262.1±82.0, Tx3= 525±166 (p=0.003). Mean aggregate tumor volume at the time of sacrifice was 1621±338 mm3 for the control group, 924±721 mm3 for Tx1, 1249±176 mm3 for Tx2 and 436±673 mm3 for Tx3. Tumor burden to body weight ratio at sacrifice was highest in control (7.1), Tx1 (4.8) and Tx2 (4.5), and least in Tx3 (1.1, p<0.05). There was lower tumor volume in all treatment groups relative to controls after post-ablation day 6 (p<0.05). Conclusions: Cryoablation is feasible in small animal preclinical breast cancer model and can extend the life span of tumor bearing mice. Higher freeze rates and more than one freeze cycle were associated with better local tumor control. Paper 20: Thermal Ablation of a Confluent Lesion in the Porcine Kidney with Magnetic Resonance Guided High Intensity Focused Ultrasound J.M. van Breugel1, M. de Greef1, G. Schubert2, M.A. Bosch1, C.T. Moonen1, M.G. Ries1. 1Imaging department, University Medical Center Utrecht, Utrecht, Netherlands; 2Philips Healthcare, Helsinki, Finland. Objective: There is an increasing interest in non-invasive kidney sparing therapy for renal cancer, since ~1.6% of men and women will be diagnosed with kidney and renal pelvis cancer during their lifetime. Therefore, several patient studies investigated the feasibility of high intensity focused ultrasound (HIFU) for the thermal ablation of renal masses. Either a hand-held extracorporeal ultrasound device with US B-mode imaging for guidance or a laparoscopic approach was used. Disadvantages are i.e. the lack of respiratory motion compensation, no real-time visualization of energy deposition, and the complexity of the probe positioning. Alternatively, feasibility of MR guided HIFU (MR-HIFU) interventions on the kidney with respect to motion compensated real-time thermometry and acoustic energy delivery was established, recently. In this study, we extend this prior work to investigate if MR-HIFU can provide for a reliable confluent volumetric lesion in the renal cortex in a clinically relevant timeframe in a porcine study. Furthermore, the energy deposition and heating pattern at larger depths were studied to ameliorate the transition to future patient studies. Methods: Ten anesthetized pigs were placed on a clinical Philips Sonalleve MR-HIFU therapy system integrated with a 1.5T Achieva MRI. Both acoustic energy delivery and MR-thermometry were respiratory gated and active surface cooling was employed to prevent near-field damage. Seven ablation cells (9-25s, 450W acoustic power, 4x4x10 mm3 per cell) were positioned in the cortex of the kidney (Figure 1). In four pigs (two from the original group of 10 and two additional pigs) the depth of the sonication measured from the skin entry was at least 6 cm (up to 7 cm). The therapeutic endpoint was evaluated by a non-perfused volume (NPV) measurement using DCE-MRI. Subsequently, the animal was euthanized and necrosis was examined using a cellular viability staining (NADH). Results: Confluent volumes on NPV-imaging (up to ~3 mL) and NADH staining (up to ~4mL) were obtained and temperatures exceeding 60°C were reached in 6 pigs (Figure 1). I.e. heating of the false rib, poor respiratory correction, and a large incidence angle caused poor kidney heating in three pigs. All four treatment clusters located at t6 cm reached temperatures above 60°C. Conclusions: These first results indicate that current clinical MR-HIFU equipment might be suitable for non-invasive therapy of renal masses even at larger depths between 6-7 cm. Positioning of the sonications and the subject based on anatomical scans is very important, as well as adequate motion compensation. Future work will include a first clinical study on renal cell carcinomas.

Paper 21: CT-Guided Microwave Ablation and Percutaneous Screw Fixation Plus Cementoplasty in the Treatment of Painful Bone Metastases C. Pusceddu1, N. Ballicu1, A. Fancellu2, L. Melis1. 1Department of Oncological Radiology, Oncological Hospital “A. Businco”, Cagliari, Italy; 2Department of Clinical and Experimental Medicine, Unit of General Surgery, Sassari, Italy. Objective: The primary goal for bone metastases treatment is usually pain relief and preservation of ambulatory functions. Our retrospective study was made to evaluate the feasibility and effectiveness of combined microwave ablation (MWA) and percutaneous screw fixation plus cementoplasty (PSFPC) in patients with painful bone metastases with fractures or to prevent pathological fracture. Methods: Fourteen patients (6 men and 8 women, median age 59 years) with 18 metastatic bone lesions underwent CT-guided MWA followed by PSFPC in the same session. All patients were no longer suitable for chemotherapy or radiotherapy and were considered unfit for surgery. All the procedures were performed under local anesthesia and conscious sedation. Vertebrae (12 cases), femurs (4 cases) and pelvis (2 cases) were the intervention sites and the primary end point was pain relief. Pain severity was estimated by using a visual analogue scale (VAS) before treatment and 6 months post-treatment. Functional outcome was assessed by improved patient walking ability. Results: All sessions were completed and all procedures were well tolerated. There were no complications related to ablation or to incorrect positioning of the screws or leakage of cement. All patients were already able to walk within 6 hours after procedure and the average length of hospital stay was 2 days. VAS score decreased from 7.4 (range, 4-9) before treatment to 1.5 (range, 0-4) 6 months after and improvement in patients’ walking ability at 6 months was 100%. No new bone fractures occurred during a median follow-up of 8 months. Conclusions: MWA followed by PSFPC is a safe and effective procedure which allows us to reduce the tumoral tissue, stabilize the fracture and prevent pathological fractures with significant pain relief and good recovery of walking capacity. MWA followed by PSFPC seems to be a promising alternative for patients who are not candidates for surgery.

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Paper 22: Magnetic Resonance Acoustic Radiation Force Imaging for Interventional Planning of HIFU Therapy in the Kidney J.M. van Breugel1, M. de Greef2, C. Mougenot2, M.A. Bosch1, C.T. Moonen1, M.G. Ries1. 1Imaging department, University Medical Center Utrecht, Utrecht, Netherlands; 2Philips Healthcare, Ontario, ON, Canada.

Paper 23: Percutaneous Radiofrequency Ablation for Metastatic Spinal Disease: An Innovative Minimally Invasive Technique by using a Navigational Spine Tumor Ablation System C. Pusceddu1, A. Fancellu2, N. Ballicu1, L. Melis1. 1Department of Oncological Radiology, Oncological Hospital “A. Businco”, Cagliari, Italy; 2Unit of General Surgery, Department of Clinical and Experimental Medicine,, Sassari, Italy. Objective: To retrospectively evaluate feasibility, safety and effectiveness of radiofrequency ablation (RFA) using the Spinal Tumor Ablation (STAR) System in palliative treatment of painful vertebral metastases. Methods: Sixteen patients (4 men and 12 women, median age 56 years), with 19 vertebral metastases underwent minimally invasive CT-guided percutaneous RFA using the STAR system. The SpineSTAR ablation instrument has an articulating probe which contains two thermocouples to actively monitor temperatures in and adjacent to the tumor. Fourteen (88%) of sixteen patients with fracture or impending fracture, underwent PMMA augmentation through the same working cannula immediately after ablation. Patients were evaluated through six months post-procedure. Reduction in pain was assessed by VAS scores pre, 1 week and 6 months post procedure. CT or MRI scans performed pre and six months post procedure were used to evaluate rates of local tumor progression. Procedural feasibility and safety was also assessed. Results: All procedures were completed and well tolerated. Articulation of the device, once in the vertebrae, allowed navigation and targeted necrosis in locations difficult to access with conventional ablation devices. There were no complications related to RFA or PMMA delivery. Pain relief was observed at one week. VAS score decreased from 7.7 (range 4.1- 8.2) to 1.3 (range 0 to 2.4) six months post procedure. No local relapse or tumor progression was observed in the treated vertebrae during median follow up of 10 months (3 – 13 months). One patient died due to progression of their primary lung cancer after 4 months. Conclusions: Use of a navigational RFA device to treat metastatic spinal lesions is a safe and effective procedure which allowed reduction of local tumor burden with significant pain relief and good local control of the metastasis. Targeted RFA seems to be a promising alternative for patients who are not candidates for surgery.

Figure 1: CT scan shows metastasis of L1 with interruption of the back wall.

Figure 1: (a) and (b) show displacement maps after MR-ARFI at 450W and 1000W, respectively. (c) and (d) show temperature maps of ablations at 450W and 1000W.

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Objective: The precision of MRI based guidance of High-Intensity Focused Ultrasound relies on the correspondence between the MR-image and the location of the HIFU ablation. However, incongruities between the planned focal point and the actual position of the HIFU beam are routinely observed. The current clinical solution of employing a low-power testshot is of limited value in high-perfused organs due to lack of temperature rise and no means to visualize the focus. Recently, MR-acoustic radiation force imaging (MR-ARFI) has been proposed in the liver as an alternative to locate the focal point non-invasively by tissue displacement in the focus. Our aims were to investigate the feasibility of respiratory-gated MR-ARFI on clinical HIFU equipment for the exact beam localization in the kidney. Of particular interest was hereby potential interference with other motion sources, such as cardiac pulsations in the renal artery. Another aim was to validate if MR-ARFI can perform this task for both linear and non-linear acoustic energy delivery. Methods: A clinical Sonalleve MR-HIFU system integrated with a 1.5T MRI (Philips Healthcare, Andover, Massachusetts) was used for MR-HIFU. A HIFU treatment cell was positioned in the renal cortex. A gradient-recalled echo planar imaging 2D dynamic scan was performed to visualize displacement due to the acoustic radiation force. All MR sequences and the acoustic energy delivery were respiratory gated. For comparison of linear and non-linear effects, 4 experiments at 2 power levels were performed: two thermal ablations with 450W continuous wave and 1000W pulsed (30% duty cycle, tone-burst of 10500 cycles), and two MR-ARFI experiments at equivalent acoustic intensity (tone-burst of 2400 cycles). Results: Displacements due to the radiation force could be reproducibly measured for both acoustic intensities and coincided with the location of the temperature elevation of the equivalent 450W and 1000W ablations, respectively (Figure 1). No interference with the cardiac cycle were observed. The focal point of the beam cone was evidenced more posteriorly than planned for the 1000W, most likely due to shock-wave formation and non-linear absorption. No significant heating was observed during the MR-ARFI experiments. Conclusions: The employed respiratory gated MR-ARFI sequence in combination with a 450 W excitation tone-burst of 2400 cycles is sensitive enough to exceed the noise level and to clearly display the focal point of the HIFU beam at a fraction of the energy compared to the 450W thermal ablation. Both at 450W and at 1000W the displacement due to the radiation force coincided with the location of the temperature rise due to thermal ablation at equivalent power. Hence, radiation force in combination with a pencil beam navigator to compensate for respiratory motion is a reliable indicator of the location of the thermal lesion and might be an alternative to the low power thermal test shot in highly perfused organs such as the kidney.

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Figure 2: RFA by using a navigational spine tumor ablation system. Paper 24: Actual versus Expected Ablation Zone Margins: Evaluation in In Vivo Porcine Liver Demonstrates Margin Overestimation M.M. Cristescu1, A. Smolock1, G. Carberry1, E. Nocerino2, C. Brace1, F. Lee1. 1University of Wisconsin, Madison, WI; 2radiology, università degli studi di milano, Milan, Italy. Objective: Ablation-zone margin evaluation is challenging due to isodensity between tumor and ablation zones on postprocedural CT examinations. The objective of this study was to measure the correspondence between estimated and actual ablative margins in an in vivo porcine liver model with a tumor phantom whose density contrasts with normal and ablated liver. Methods: Tumor phantoms (n=14) were created within six porcine livers in vivo and, under ultrasound guidance, microwave ablation of each phantom was performed (Image 1). Contrast-enhanced CT was performed before and after ablation to assess tumor size, ablation zone size, and tumor margins. Diameters of each zone were measured, and estimated margins calculated as (ablation diameter – tumor diameter)/2. Actual margins between the visible tumor phantom and ablation zone were also measured. Estimated, mean actual, and minimum margins were compared using paired t-tests. Results: Mean (r standard deviation) tumor phantom diameter was 8.7r1.8mm and mean ablation zone diameter was 22.1r4.6mm. Tumor phantom diameters decreased by approximately 5% during ablation (P<0.01). On average, actual margins were 24% smaller than estimated margins (5.1r2.0 mm vs 6.7r2.1 mm, P<0.001). Importantly, the mean minimal margin was 0.9r1.5mm, 86% smaller than the estimated margin (P<0.001). Zero or positive margins were noted in 64% (9/14) of ablations. Conclusions: Estimating ablation margins by raw comparison of ablation zone and pre-ablation tumor dimensions significantly overestimates actual ablation margins. Tissue contraction, shortcomings in imaging guidance, and operator error may all potentially contribute to this estimation errors. Careful evaluation using anatomic landmarks, fiducial markers, or 3D rendering may be warranted for studies aiming to more precisely evaluate ablative margins.

All values in mm

Image 1. Tumor mimic formation within porcine liver demonstrated in the ex-vivo setting via ultrasound (top left). Post-ablation contrast-enhanced CT imaging (top right) demonstrates the post-ablation appearance of the porcine tumor phantom and surrounding ablation zone. The gross appearance of the corresponding axial section (bottom) demonstrates the methylene-blue stained tumor mimic surrounded by tan-colored ablation zone. Paper 25: Three Dimensional Quantitative Tumor Response and Survival Outcome of Intermediate-Stage HCC after Repeated Transarterial Chemoembolization Y. Zhao3, R. Haroun3, S. Sahu3, R. Duran3, R. Schernthaner2, J. Chapiro3, S. Smolka1, M. Lin4, J. Geschwind5. 1Charite University Hospital Berlin, Berlin, Germany; 2Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; 3Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT; 4U/S Imaging and Interventions (UII), Philips Research North America, Newyork, NY; 5Department of Diagnostic Radiology and Imaging Science, Yale University School of Medicine, New Haven, CT. Objective: To evaluate the treatment response of intermediate-stage hepatocellular carcinoma (HCC) to repeated transarterial chemoembolization (TACE), as determined with three-dimensional (3D) quantitative European Association for the Study of the Liver (qEASL) criteria, and to compare the overall survival (OS) of nonresponders versus that of responders. Methods: A total of 94 consecutive patients (87.2% men, mean age, 62 years) with Barcelona Clinic Liver Cancer stage B HCC were retrospectively included. Tumor response was assessed by qEASL, a volumetric enhancement criterion. qEASL defines response as a t65% decrease in enhancing tumor volume. Results: Median follow-up period was 25 months (range 2.1-106.2). Twenty-eight (29.8%) patients were responders after the first TACE. These patients showed a clear trend towards a longer OS than nonresponders (36.7 vs. 21.5 months, P=0.071). Forty-three initial nonresponders underwent a second TACE within 3 months and had complete follow-up imaging. After the second TACE, 15 (34.9%) patients achieved response and their median OS was significantly longer than 28 nonresponders (47.8 vs. 13.6 months, P=0.010). Furthermore, there was no significant difference in OS between the 28 patients who achieved response after the first TACE and those 15 initial nonresponders who achieved response after the second TACE (36.7 vs. 47.8 months, P=0.701). The difference in OS between the responders and nonresponders after the third TACE was not significant (11.4 months vs. 13.5 months, P=0.986). Conclusions: A second TACE can be beneficial in terms of tumor response (with qEASL criteria) and survival for HCC patients who showed initial nonresponse.

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Paper 26: Drug-Eluting Bead Transarterial Chemoembolization (DEBTACE) vs Conventional Transarterial Chemoembolization (cTACE): Is There an Improved Survival in Patients with Unresectable Hepatocellular Carcinoma (HCC)? O.A. Picado Roque1, P.E. Finkelstein1, D. Yakoub1, S. Venkat2. 1Surgery, University of Miami, Miami, FL; 2Radiology, University of Miami, Miami, FL.

Tumor reduction according to RECIST criteria

Paper 27: Percutaneous Ablation of Small HCCs: Comparison of Three Commercially Available Microwave Devices L. Tarantino2, P. Ambrosino3, P. Gallo1, P. Tarantino3, A. Nasto4. 1 Campus Biomedico University, Rome, Italy; 2Interventional Hepatology Unit, “A.Tortora” Oncology Hospital, Pagani, Italy; 3Federico II University, Naples, Italy; 4“A.Tortora” Oncology Hospital, Pagani, Pagani, Italy. Objective: We compared the effectiveness of 3 Microwawe (MW) commercially available devices for percutaneous treatment of small HCCs. Methods: 24 patients with cirrhosis and a single HCC nodule (diameter <2 cm; range: 1.3 – 2 cm) were treated by a single insertion of one of the following MW devices: 1) 10 patients with 14G - 915 MHz antenna with 45 Watt MW generator (Vivawawe, Covidien, USA); 2) 5 patients with 14G - 2450 MHz antenna with 100 Watt generator (AMICA, Hospital Service, Italy); 3) 9 patients with 13G 2450 MHz antenna with 180 W generator (Acculis, Microsulis Medical Ldt, England). Therapeutic efficacy in terms of size of the ablation areas were evaluated with contrast enhanced ultrasound (CEUS) at 48 hours from the ablation time. Results: The diameter of HCC nodules ranged from 11 to 20 mm (mean: 15 mm). Post ablation CEUS and CT showed complete necrosis in all cases. Different size of ablation were obtained with different devices (table 1). Differences in transverse diameter of the area of necrosis between the Covidien device and the other two devices was statistically significant (p=0.01). There was no statistically significant difference between AMICA HS and Acculis devices. However, the time of application to obtain a similar result was consistently lower with Acculis device than with AMICA HS. Conclusions: All devices seem to be effective and safe in the treatment of small HCC by a single antenna insertion. Howewer, the sizes of necrosis obtained were consistently lower than those indicated from manufacturers (Table 1). Sizes of ablation areas obtained with the different devices (CEUS examination).

Paper 28: Post-Ablation Safety Margin of Radiofrequency Ablation of Hepatocellular Carcinoma: Precise Assessment with a Three Dimensional Reconstruction Technique K. Ming2, Z. Peng1. 1the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China; 2the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. Objective: To analyze the precise ablative margin (AM) after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) by fusing three-dimensional (3D) images of tumor and ablated zones with a reconstruction technique. Methods: From March 2011 to May 2013, 134 patients with 159 primary or recurrent HCC tumors within Milan criteria received RFA were enrolled. Contrast-Enhanced Computer Tomography (CECT) scan was performed before and 1 month after treatment. CECT data were processed with 3D reconstruction software. Three dimensional tumor and ablated zones were reconstructed and fused to show the ablation margins. Results: On the fusing image, the min-AM after RFA ranged from 1 to 9.3 mm (medianrSD, 4.8r1.8mm). Local tumor progression (LTP) was observed in 19 tumors. The median min-AM was 3.1r1.6 mm for patients with LTP, while the median min-AM of patients without LTP was 5.1r1.8 mm (p = 0.023). A 5mm min-AM was achieved in 36.5% (58/159) tumors. After treatment, the 1-, 2-, 3-year cumulative LTP rates were 8.6%, 18.0%, 23.5%, respectively. On the subgroup analysis, the 1-, 2-, 3-year LTP rates were 10.9%, 25.9%, 35.1% for patients with min-AM <5mm, and 4.1%, 4.1%, 4.1% for patients with min-AM t5mm, respectively (p=0.016). Multivariate analysis identified that only min-AM <5 mm was an independent risk factor for LTP after RFA (p=0.044, HR=4.587, 95% CI, 1.045-22.296). Conclusions: Post-ablation evaluation of AM with 3D technique provides more information for local response after RFA. To achieve the best local efficacy, a post-ablation safety margin t5mm is recommended. Paper 29: Combined Radiofrequency Ablation and Ethanol Injection versus Hepatic Resection for Medium and Large, Solitary Hepatocellular Carcinomas Z. Peng, K. Ming. the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. Objective: To compare hepatic resection (HR) and combined use of radiofrequency ablation and percutaneous ethanol injection (RFA-PEI) in the treatment of resectable solitary hepatocellular carcinoma (HCC) with medium or large size (3.1-7.0cm). Methods: Between June 2009 and June 2015, 201 consecutive patients were enrolled including 102 undergoing RFA-PEI and 99 undergoing HR. The differences in survival between groups and subgroups were compared with the Kaplan-Meier method and log-rank tests. Univariate and multivariate analyses were performed to indentify the prognostic predictors for survival. Results: OS rates at 1, 3, and 5 years were 96.0%, 79.9% and 58.7% with RFA-PEI and 81.8%, 59.6% and 48.1% with HR, respectively (p=0.033). The corresponding 1-, 3-, and 5-year RFS after RFA-PEI and HR were 75.3%, 59.0%, 52.2% and 54.5%, 43.4%, 39.3%, respectively (P=0.016). Subgroup analyses showed that the 1-, 3-, and 5-year OS in RFA-PEI group (97.5%, 87.2%, 71.8%) were better than those in HR group (86.8%, 66.0%, 60.4%) with 3.1-5.0cm tumors (p=0.011), so did the 1-, 3-, and 5-year RFS (RFA-PEI vs. HR: 84.4%, 66.3% and 63.0% vs. 62.3%, 50.9% and 43.2%, respectively; p=0.009). There was no significant difference between these two groups regarding OS (p=0.209) and RFS (p=0.152) with 5.1-7.0cm tumors. Multivariate analyses showed that treatment type was the independent predictor for both the OS (p=0.022) and RFS (p=0.014), and the tumor size was also the significant prognostic factor for RFS (p=0.028). Conclusions: RFA-PEI had the survival benefit over HR in the treatment of solitary HCC with medium size whereas showed comparableefficacy to HR in the treatment of HCC with large size.

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Objective: Despite the extensive use of screening studies, more than two thirds of HCC are detected at an advanced stage. Transarterial Chemoembolization (TACE) has been a widely used to treat unresectable HCC. Drug-eluting beads or DEBTACE has shown improved tolerability over conventional TACE (cTACE). This study aims to compare the overall survival in patients treated with either DEBTACE or TACE for unresectable HCC. Methods: A comprehensive online search of MEDLINE, EMBASE, PubMed, SCOPUS and the Cochrane database was conducted (2005-present). Comparative studies in patients with unresectable HCC undergoing DEBTACE vs cTACE were reviewed; Study quality was assessed using STROBE checklist. Pooled risk ratios and 95% confidence intervals (CI) for survival at 1, 2 and 3 years were calculated. Results: Overall, 14 studies with 1,537 HCC patients were included; 748 underwent DEBTACE and 789 underwent cTACE. Mean age was 67 r 11.2 years with a male/female ratio of 4/5. Meta-analysis of overall data showed no difference in overall survival in patients undergoing cTACE compared with DEBTACE at 1-YR (RR:1.08, CI:0.96-1.14, P=0.185), 2-YR (RR:1.19, CI:1.02-1.26, p=0.11) and 3-YR (RR:1.16, CI:0.84-1.29, P=0.14). There was no significant difference in tumor reduction (according to RECIST criteria), incidence of postembolization syndrome or liver decompensation between the groups. Conclusions: Although randomized controlled trials have shown improved tolerability for DEBTACE, no survival advantage has been shown for this technique over cTACE in unresectable HCC patients.

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Paper 30: Device-Specific Differences in Manufacturer-Recommended Activity for Glass versus Resin Yttrium-90 Transarterial Radioembolization: A Single Cohort Analysis Incorporating Real Patient Data

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A.D. Talenfeld1, J.A. Rotman1, E.A. Mauer2, B.W. Cobb1, R.A. Charalel1, P.J. Christos2, D.C. Madoff3. 1Radiology, Weill Cornell Medicine, New York, NY; 2Healthcare Policy and Research, Weill Cornell Medicine, New York, NY; 3Radiology, Weill Cornell Medicine, New York, NY. Objective: Two devices, glass and resin yttrium-90-loaded microspheres, are commercially available for transarterial radioembolization (TARE) of primary and metastatic cancers in the liver. The dosimetric model for each of these differs fundamentally from the other. Resin microsphere dosimetry has been criticized as too conservative; however, the prevalence of radioembolization-induced liver disease requires balancing the risk of under-treatment with the converse risk of dose-related toxicity. For valid logistical reasons, institutions may be tempted to offer either one device or the other for all TARE cases. Treating interventional radiologists, who know intimately their patients’ clinical conditions and hepatic arterial perfusion, may often be unaware of significant differences in the amount of radiation prescribed depending on which device is being used. Our study aims to compare the two device manufacturers’ recommended activities using a real sample of previously treated patients. Methods: A retrospective chart review was performed of all patients treated for primary and metastatic intrahepatic malignancy with TARE at our single center between 10/2011 and 9/2014. Patients were included who had lobar or bilobar disease (tumor arterial supply arising from 3 or more segments per lobe). Regardless of the actual historical device used or activity prescribed, separate hypothetical doses were calculated for each patient assuming treatment with glass or resin microspheres using the manufacturer’s recommended calculators. No dose reductions were performed. All whole liver, lobar and tumor volumes were obtained from pre-treatment liver protocol MR or CT images by a technologist in our hospital’s 3D post-processing imaging laboratory. Patients were excluded if their charts lacked documentation of height or weight. Median prescribed doses were compared between devices for all patients before and after stratifying by primary tumor type using the Wilcoxon signed-rank test. Sub-analyses were performed in which dosimetric inputs (whole liver volume, treated liver volume, tumor volume, height, weight and BSA) were assessed for their Spearman correlation with differences in prescribed dose. Differences in median input values were also compared between patients by tumor type. Results: Median prescribed dose for glass and resin microsphere treatment was significantly different, 2.8 vs. 1.1 GBq, p<0.0001. This difference was also present when the sample was divided into those treated for hepatocellular carcinoma and those with all other cancers (3.0 vs. 1.1 GBq, p<0.0001, and 2.5 vs. 1.1 GBq, p<0.001, respectively). Treated liver volume and whole liver volume correlated strongly with differences in prescribed dose (rs= 0.934 and 0.777, p<0.0001). Tumor volume weakly correlated with dose differences (rs=0.435, p=0.005). Height, weight and BSA did not correlate with differences in prescribed dose. Patients in our sample who were treated for HCC did differ from other patients by their median whole liver volume (2006 vs. 1734 mL) and weight (78 vs. 72 kg), p<0.05; however, tumor type being HCC vs. other was not by itself associated with significant differences in prescribed dose (p=0.08). Conclusions: Treatment with glass radiomicrospheres implies prescription of doses that are typically 2.5 times those prescribed for resin microspheres. Though the two devices have several distinguishing features, and though each device’s dosimetric model has its limitations, this significant difference in prescribed radioactivity should be considered by physicians and institutions providing TARE. Paper 31: New OPTN/UNOS MELD Scoring System for Hepatocellular Carcinoma: Impact on Transplantation Allocation and Post-Transplant Survival M. Xing, J.M. Ludwig, H.S. Kim. Interventional Radiology, Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT. Objective: To investigate the effect of the new Organ Procurement and Transplantation Network (OPTN)/ United Network for Organ Sharing (UNOS) hepatocellular carcinoma (HCC) exception score cap on transplant patients within the Model for End-Stage Liver Disease (MELD) era. Methods: The most recently updated UNOS database was used to identify patients with HCC who were listed for OLT between 2002 and 2014 and transplanted up to September 2015. Mean biological and exception MELD scores for transplanted patients was obtained and stratified by region and year of transplant. The new HCC MELD exception cap was applied to all patients with MELD exception scores of t35. The characteristics of patients who would have been affected by the change in scoring was recorded and compared to that of actual OLT patients. Survival analysis was conducted via Kaplan-Meier method and log-rank test.

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Results: Of 37,870 HCC patients who were granted MELD exception points during the study period, 25,476 patients (67.3%) eventually received OLT. When the cap of 34 points for HCC exception scores was applied, a total of 7,745 (30.4%) transplanted patients would have had delayed or no allocation to transplant. Significantly larger tumor size in the simulated transplant group with HCC score cap vs. the actual transplanted group was observed (mean index size 3.7 cm vs. 2.6 cm, p<0.001). Significantly higher body mass index (BMI) was observed in the simulated transplant group with HCC score cap vs. the actual transplanted group (mean BMI 28.8 vs. 26.5, p<0.001). Mean survival from OLT for the remaining 17,731 patients was significantly higher than that of actual transplanted patients (127.6 months vs. 125.6 months, p<0.002). Conclusions: Significantly higher survival was observed when the MELD score cap of 34 was applied on HCC exception patients, giving priority to higher biological MELD patients, which would have enhanced overall survival of the entire liver transplant population.

Paper 32: Inter-Modality Comparison of Enhancement Patterns between Baseline MR and Follow-up CT in Patients with Hepatocellular Carcinoma (HCC) Treated using Conventional Transarterial Chemoembolization (cTACE): A Quantitative Voxel-Wise Approach S. Smolka1, J. Treilhard3, W. Manzano2, J. Chapiro4, B. Gebauer5, J. Geschwind6, J. Duncan7, M. Lin8. 1Charite University Hospital Berlin, Berlin, Germany; 2School of Medicine, University of California, Irvine, Irvine, CA; 3Yale School of Engineering and Applied Sciences, New Haven, CT; 4Charite University Hospital, Berlin, Germany; 5Charite University Hospital, Berlin, Germany; 6Yale School of Medicine, New Haven, CT; 7Yale School of Engineering and Applied Sciences, New Haven, CT; 8Philips Research North America, Cambridge, MA. Objective: Lipiodol deposition covering all viable tumor tissue is vital for treatment success in cTACE. So far, the evaluation of Lipiodol deposition has been done either qualitatively or quantitatively, but generalized on a whole lesion basis. Thus loosing localization information. Our study investigates the enhancement patterns observed inside targeted HCC lesions and correlates them on a voxel-wise basis between baseline multi-phasic MR, where enhancement is indicative of viable tumor tissue, and follow-up CT, where enhancement is indicative of Lipiodol deposition. Methods: In our single center retrospective study, 20 consecutive patients with a total of 27 HCC lesions (who received conventional TACE between June 2014 and June 2015) were included. Patients received baseline multi-phasic MR 4 weeks prior to TACE and CT 24 hours afterwards. MR and CT images were registered with the transformation generated by the robust point matching algorithm (BioImage Suite, Yale School of Medicine) aligning the liver surfaces of both images. Tumors were segmented semi-automatically using GeoBlend (Medisys, Philips Research, Suresnes, France). The definition of voxel enhancement on MR and CT images was calculated based on the mean intensity of extra-tumoral liver parenchyma. In both MR and CT, each lesion voxel was classified as enhancing or non-enhancing, and the inter-modality enhancement patterns of each voxel were individually correlated. Voxel enhancement behavior was correlated with the Dice Similarity Coefficient (DSC) of its segmentation on MR and CT. Results: For each tumor, the fraction of voxels which exhibited consistent inter-modality enhancement showed positive correlation with the DSC (P=0.003). Linear regression analysis demonstrated a positive correlation between these quantities (slope = 0.57 r 0.17). Well registered tumors (DSC>0.8) contained a majority (average=70.8%) of voxels which individually showed a consistent enhancement behavior on both MR and CT imaging.

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Conclusions: We showed voxel-wise enhancement correlation between baseline MR and follow-up CT, indicating Lipiodol deposition in viable tumor tissue. This can enable a 3D quantitative approach to drug-uptake mapping and tumor response prediction.

Paper 33: Magnetically Triggered Oxaliplatin Release for the Treatment of Colorectal Liver Metastasis: An In Vitro and In Vivo Feasibility Study S.B. White1, W. Park2, D. Kim2, A.C. Larson2. 1Radiology, Medical College of Wisconsin, Milwaukee, WI; 2Radiology and Radiological Sciences, Northwestern University, Chicago, IL. Objective: Though systemic chemotherapy is the standard of care for the treatment of metastatic colorectal cancer, only 63% of patients are able to get a full 12 cycles. New drug delivery platforms are needed to mitigate systemic toxicities. The objective of this study was to develop a new magnetically triggered oxaliplatin nanoparticle to treat colorectal liver metastases Methods: Liposome-magnetic nanoparticles were synthesized and had a diameter of ~140 nm. Magnetic properties were confirmed via exposure to a magnetic field. The efficacy of drug release was determined by exposing the liposomes to an alternating magnetic field (AMF), Oxaliplatin was quantified with high-performance liquid chromatography (HPLC). To test in vitro efficacy, CC-531 (colorectal liver metastasis cell line) cells were seeded in a 96-well plate and incubated in 5% CO2 at 37°C for 24h. After incubation, the cells were treated with the liposomes and exposed to the AMF under the same conditions as above. 48 hours after incubation, the cell counting kit-8 (CCK-8) assay was performed to determine the cell viability. For in vivo studies, 20 rats were inoculated with 5*106 CC-531 cells into their left hepatic lobe. The rats were divided into 4 groups: nanoparticle infusion with subsequent exposure to AMF (~1.85 kW, 200 kHz) for 30 min (group 1), nanoparticle infusion alone (group 2), oxaliplatin IV (group 3) and no treatment (group 4). The nanoparticles were administered via the portal vein and rats were optically imaged immediately after infusion to ensure hepatic delivery and release. Quantitative R2 and R2* measurements after nanoparticle infusion and before triggered release were performed. At 24 hours, 1, 2 and 3 weeks after treatment each animal was imaged. At all time points, tumors were measured. At week 3, the rats were euthanized, tumors harvested and H&E and Prussian blue staining was performed and evaluated for tumor necrosis. Results: Drug loaded magnetic liposomes presented an oxaliplatin loading content of ~2 %. Magnetic liposomes separated from the solution within 30 min, when the sample was exposed to a permanent magnet. An increase in drug release (~18%) was observed after the samples were exposed to the AMF. CCK-8 assay demonstrated that under high-dose oxaliplatin conditions (0.17 -0.33 mg/mL), the cell viability after liposome treatment and exposure to AMF were significantly lower than those not exposed to AMF (p<0.001). No difference was observed for low-dose conditions (0.08-0.01 mg/mL). MR imaging revealed that all the rats developed tumors within 1 week. Optical imaging confirmed that the nanomaterial was infused locally into liver and had triggered release. All rats demonstrated metastatic disease by week 3, and 2 rats in the control died without reaching the 3 week endpoint. Percentage tumor size change from week1 to week 2 was 10%, 28%, 29% and 23.5% in groups 1-4 respectively. Conclusions: AMF triggers oxaliplatin release from liposome-magnetic nanoparticles for increased cell kill of CC-531 colorectal metastases line. Triggering is well tolerated by rats and further can be employed to targeted killing of tumor by optimizing the dose of drug.

Paper 34: Embolotherapy for Neuroendocrine Tumor Liver Metastases: Prognostic Factors for Hepatic Progression-Free Survival and Overall Survival J.X. Chen1, S.C. Rose4, S.B. White5, G. El-Haddad6, F. Nicholas7, H. Yarmohammadi3, D.Y. Sze2, N. Kothary2, K. Stashek1, W.E. Paul1, R. Salem8, D. Metz1, M.C. Soulen1. 1University of Pennsylvania, Philadelphia, PA; 2Stanford Medical Center, Stanford, CA; 3Memorial Sloan Kettering Cancer Center, New York, NY; 4University of California San Diego, San Diego, CA; 5Medical College of Wisconsin, Milawaukee, WI; 6Moffitt Cancer Center, Tampa, FL; 7University of California San Francisco, San Francisco, CA; 8Northwestern Memorial Hospital, Chicago, IL. Objective: Optimal embolotherapy for neuroendocrine tumor (NET) liver metastases remains controversial. This study evaluated the impact of disease and treatment related factors on survival outcomes following embolotherapy. Methods: This was a multicenter retrospective study of 150 patients (60 years mean age, 57% male) with NET liver metastases from gut (n=68), pancreas (n=67), lung (n=8), or other (n=7) primary sites treated with conventional transarterial chemoembolization (TACE, n=47), transarterial embolization (TAE, n=41), or transarterial radioembolization (TARE, n=62) between 2004-2015. Hepatic progress-free survival (HPFS) and overall survival (OS) were evaluated using Kaplan-Meier method. Prognostic factors including tumor grade, hepatic tumor burden, and embolotherapy technique were assessed with univariate and multivariate Cox proportional hazards models. Embolotherapy toxicity was evaluated using National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Results: Median follow-up time was 22 months (range: 2 – 125 months). Higher tumor grade corresponded to decreased HPFS and OS, with median HPFS of 18.5, 11.4, and 4.9 months (p<0.0001) and OS of 125.1, 32.9, and 21.4 months (p<0.0001) for grades 1 (n=74), 2 (n=56), and 3 (n=20) respectively. Hepatic tumor burden >50% demonstrated decreased OS versus <50%, with median OS of 59.5 months (<25% burden) and 51.6 months (25-50% burden) versus 30.5 months (50-75% burden) and 20.3 months (>75% burden), p=0.01. No significant differences in HPFS or OS were seen among gut, pancreas, or lung primaries. In multivariate analysis, there was an interaction between embolization technique and tumor grade. TARE demonstrated significantly longer HPFS compared to TACE for grade 1 and 2 tumors (median HPFS of 26.1 and 15.7 months vs. 8.4 and 8.1 months respectively, p<0.05) with hazard ratios of 0.43 (grade 1) and 0.41 (grade 2) versus TACE in multivariate analysis. TARE demonstrated significantly shorter HPFS and OS versus TACE for grade 3 tumors (median HPFS and OS of 3.4 and 3.4 months versus 5.0 and 25.5 months respectively, p<0.05) with hazard ratios of 4.92 (HPFS) and 10.02 (OS) versus TACE in multivariate analysis. HPFS and OS after TAE were not significant different from TACE and TARE in multivariate analysis. HPFS and OS were not significantly affected by the choice of Yttrium-90 microsphere agent, TACE chemotherapy regimens, or by the number of treatments. The number of total and severe (CTCAE grade 3 or higher) clinical toxicities was not significantly different between embolotherapy modalities. Pain was more frequent following TAE (71%) versus TACE (45%) and TARE (36%), p=0.003, but severe pain was equivalent between modalities. Conclusions: TARE demonstrated improved HPFS in grade 1 and 2 tumors, but worse HPFS and OS in grade 3 tumors compared to TACE. Higher tumor grade and tumor burden were associated with worse HPFS and OS. No significant differences in HPFS or OS were seen among tumor primary sites. Prospective studies are needed to determine the optimal endovascular treatment for patients with NET liver metastases. Paper 35: Drug-Eluting Microspheres Loaded wit hIronetecan (TandemIRI) for Treating Hepatic Metastases from Colorectal Cancer: Interim Analysis of the MIRACLE III Trial G. Varano1, G. Mauri1, P. Della Vigna1, G. Bonomo1, M. Zampino2, P. Ravenda2, F. Cristiana2, F. Orsi1. 1Interventional Radiology, Istituto Europeo di Oncologia, Milan, Italy; 2IEO, Milan, Italy. Objective: To report the interim results of the MIRACLE III trial. Primary endpoints of the study were the safety of the treatment and the local tumor control at three months. Secondary endpoints were the local tumor control with possible follow up to 1 year, survival and time to progression. Methods: Between November 2013 and February 2015 18 patients (11 males, 7 females, mean age 62 years, range 47-79) with a mean of 9 (range 1-30) hepatic metastases from colorectal cancer were prospectively enrolled. Enrolled patients underwent at least two prior lines of chemotherapy. Seven patients had disease involving one liver lobe, while 11 had disease involving both liver lobes. Fourteen patients had extra-hepatic disease spread at the time of first embolization. Thirteen patients previously underwent hepatic surgical resection or image-guided ablation. Mean diameter of the treated lesions was 47.6 mm (range 12-161 mm). Procedure was performed by using microparticles of 40mm loaded with 100-150 mg of

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MR and CT are registered using the liver surface as a reference. Once registered, we correlate the value of each voxel inside the segmented lesion between the baseline MR and the follow-up CT. Axial, coronal and sagittal slices show spatially corresponding areas of tumor tissue, representing viable tumor that was treated successfully with lipiodol.

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Irinotecan. Superselective embolization was performed when possible. Treatment was given every 4 weeks up to disease progression. Adverse events (AE) were evaluated according to the NIH criteria. Response to treatment was evaluated according to RECIST criteria. Estimated median for time to local tumor progression was calculated using Kaplan-Meyer analysis. Results: Actual mean follow up is 8.6 r 5.8 months. Up to now, 69 treatments were performed (mean of 3.8 treatments per patient, range 2-9 treatments). G1/G2 AEs occurred in 42/69 (60.8) procedures. No G3, G4 or G5 complications occurred. Local tumor control was achieved in 14/18 (77.8%) patients at 3 months and in 10/18 (55.6%) patients at 6 months. Median time to local tumor progression was 7 months. Conclusions: Drug-eluting microspheres loaded with Irinotecan are safe in the treatment of patients with hepatic metastases from colorectal cancer, with more than 70% of local tumor control at 3 months. Paper 36: Simultaneous Trans-hepatic Portal and Hepatic Vein Embolization Before Major Hepatectomy: The Liver Venous Deprivation Technique B. Guiu1, P. Chevallier2, A. Denys3, M. Pierredon1, V. Schembri1, J. Ramos1. 1Radiology, St-Eloi University Hospital - Montpellier, FRANCE, Montpellier, France; 2University Hospital of Nice, Nice, France; 3 CHUV, Lausanne, Switzerland. Objective: To assess technical feasibility, safety, and efficacy of the liver venous deprivation (LVD) technique that combines both portal and hepatic vein embolization during the same procedure for liver preparation before major hepatectomy. Methods: Seven patients (mean age: 63.6y [42-77y]) underwent trans-hepatic LVD for liver metastases (n=2), hepatocellular carcinoma (n=1), intrahepatic cholangiocarcinoma (n=3) and Klatskin tumour (n=1). The PVE procedure was conducted using a mixture of 1-4 mL of iodized oil (Lipiodol, Guerbet, Aulnay-sous-bois, France) and 1 mL of n-butyl-cyanoacrylate (Glubran II, GEM, Italy). Segment IV was not embolized. The right hepatic vein (HV) was accessed through the liver using a micropuncture set. This access was used to introduce a trans-hepatic 7F Destination sheath over an Advantage 0.035” guidewire. An Amplatzer Vascular Plug II (St-Jude Medical, Plymouth, MN) of 18-22mm was deployed with its distal part 10mm before the junction with the inferior vena cava, to facilitate further surgical HV ligature. Then, embolization of the distal branches of the right HV, as well as collaterals (inter-hepatic vein communications when visible) was conducted using a 1:1 mixture of lipiodol:n-butyl-cyanoacrylate. Assessment of future remnant liver (FRL) volume, liver enzymes and histology was performed. Results: Technical success was 100%. No complication occurred before surgery. Resection was performed in 6/7 patients. CT-scan revealed hepatic congestion in the venous-deprived area (6/7 patients). A mean of 3 days (range:1–8 days) after LVD, transaminases increased (AST: from 42r24U/L to 103r118U/L, ALT: from 45r25U/L to 163r205U/L). Twenty-three days (range:13–30days) after LVD, FRL increased from 28.2% (range:22.4-33.3%) to 40.9% (range:33.6–59.3%). During the first 7 days, venous-deprived liver volume increased (+13.4%) probably reflecting vascular congestion, whereas it strongly decreased (-21.3%) at 3-4 weeks. Histology (embolized lobe) revealed sinusoidal dilatation, hepatocyte necrosis and important atrophy in all patients. Conclusions: Trans-hepatic LVD technique is feasible, well tolerated and provides fast and important hypertrophy of the FRL. This new technique needs to be further evaluated and compared to portal vein embolization. Paper 37: Feasibility of Combining Capecitabine and Temozolomide with Yttrium 90 Radioembolization (CapTemY90) for Intermediate-Grade Metastatic Neuroendocrine Tumors M.C. Soulen, D. van Houten, S.W. Stavropoulos, J.I. Mondschein, U.M. Teitelbaum, A. Loaiza-Bonilla, B. Giantonio. University of Pennsylvania, Philadelphia, PA. Objective: Grade 2 neuroendocrine tumors (NET) have an intermediate proliferative rate and progress more aggressively than low-grade NETs. The combination of capecitabine and temozolomide (CapTem) has been shown to achieve response rates of 61% in well-differentiated NETs. Capecitabine is synergistic with radiation and often used concurrently in other malignancies. We investigated the safety and tolerability of combining CapTem with Y90 radioembolization for progressive Grade 2 NETs with liver-dominant metastases. Methods: Patients were treated with capecitabine 600 mg/m2 twice daily for 14 days and temozolomide 150-200 mg/m2 in two divided doses on Days 10-14, with 14 days between cycles. Simulation angiography and MAA scan for Y90 planning were performed during the first cycle of chemotherapy. During the second cycle, Y90 radioembolization with resin microspheres was performed to one lobe on Day 7. The other lobe was treated if needed on Day 7 of the 3rd or 4th cycle. CapTem was continued monthly. Clinical and laboratory toxicities were assessed monthly. Imaging

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was performed 3 months after the first radioembolization, then every 3 months. This retrospective analysis was IRB approved. Results: 15 patients were treated. Primary NETs were pancreatic (6), bronchial (3), small bowel (3), rectal (2), unknown (1). 12/14 patients completed the prescribed combination of oral chemotherapy and radioembolization. One heavily pre-treated patient developed Grade 2 hyperbilirubinemia after the first radioembolization and did not have the other lobe treated. One had severe post-embolization syndrome after the first radioembolization and declined the second one. 10/14 patients stopped CapTem at 3-31 months due to toxicity or progression, the other 4 remain on CapTem for 2 months – 4 years. As expected, G1-G2 fatigue, nausea, or thrombocytopenia was observed in most patients. Three patients had G3 toxicities, one each thrombocytopenia, fatigue, and pain. Mean decrease in CgA was 86%. One patient progressed in the liver at 21 months, the remainder are free from intrahepatic progression at 6-25 months. Three patients died, two from extrahepatic progression (7, 32 months) and one from REILD (17 months). Conclusions: : CapTemY90 is a tolerable regimen with toxicities similar to those reported for CapTem or Y90 alone. Responses are encouraging and supports further evaluation in a multicenter Phase 2 trial. Paper 38: Cryoablation for Local Disease Control of Renal Cell Carcinoma Bone Metastases C.S. Gardner3, J. Ensor2, S.Y. Huang1, K. Ahrar1, S.H. Sabir1, S. Gupta1, V.O. Lewis1, A.L. Tam1. 1MD Anderson Cancer Center, Houston, TX; 2 Houston Methodist Research Institute, Houston, TX; 3Baylor College of Medicine, Houston, TX. Objective: To assess local disease control following cryoablation of bone metastases in patients with metastatic renal cell carcinoma (mRCC). Methods: This is an IRB-approved retrospective study. From January 2007 to December 2014, 50 osseous metastases in 40 patients (30 M, 10 W, average age 62, range 47-82 years old) were treated by 42 percutaneous cryoablation procedures for the intent of local disease control. Twenty-five patients (62.5%) had oligometastatic disease, defined as < 5 metastases at the time of ablation, and fifteen patients (37.5%) had diffuse (> 5) but controlled metastases with the exception of a disproportionately progressing osseous metastasis. Local disease control was assessed by imaging and clinical follow-up. Overall survival and recurrence free-survival were analyzed. Complications were recorded according to Common Terminology Criteria for Adverse Events, version 4.0. Results: The overall local disease control rate was 77.5% (31/40). The local disease control rate in patients with oligometastatic disease was 96% (24/25). There were three (7.5%) recurrences limited to the ablation site and six (15%) recurrences at the ablation site that occurred concurrently with progression at other distant metastatic sites. A mean of 1.3 osseous metastases (range 1-3) were treated per patient, with average lesion size 3.4 cm (range 1-8 cm). The median follow-up time was 35 months [95% CI: (22.7, 74.4)]. The median overall survival was 27.4 months [95% CI: (15.7, 55.2)]. The recurrence free survival was significantly different between patients with oligometastatic disease (27.4 months) and those with diffuse metastases (10 months) at the time of ablation, p=0.04. The difference between the maximum ablation size and tumor size was a significant predictor of local recurrence (p=0.04) by logistic regression analysis. There were 3 Grade 3 (femoral nerve injury resolved after rehab (n=2), hemothorax necessitating chest tube placement (n=1)); and, 1 Grade 4 (active hemorrhage requiring transfusion and embolization) complications. Conclusions: Cryoablation can be used to achieve local disease control of osseous metastases in patients with mRCC. Patients with oligometastatic disease may derive the most benefit. Paper 39: Initial U.S. Experience Comparing using the KIVA Vertebral Augmentation System in Patients with Multiple Myeloma to Vertebroplasty A. Brown1, W. Lea1, S.B. White2, C. Arce-Lara1, S. Tutton1. 1Medical college of Wisconsin, Wauwatosa, WI; 2Medical college of Wisconsin, Milwaukee, WI. Objective: After FDA approval, the KIVA system was used in MM patients to potentially reduce cement volume, leakage, and adjacent level fractures. We investigated pain and medication use after vertebral augmentation in patients with pathologic vertebral compression fractures due to multiple myeloma (MM). Methods: After IRB approval was obtained, medical records were retrospectively reviewed for vertebral augmentation procedures performed between 2012 and 2015 on patients with compression fractures related to MM. Type of augmentation and pre and post procedural medication usage were assessed. Pain and disability was assessed using the Brief Pain Inventory (BPI) and Roland Morris disability questionnaires (RMDQ). New compression fractures, re-treated levels and adjacent

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Paper 40: Clinical Experience of a New Prophylactic Device for Impeding Pathological Hip Fracture F. Deschamps2, T. Carteret3, B. Lapuyade4, T. De Baere2, L. Tselikas2, F. Cornelis1. 1Imagery, CHU Bordeaux Pellegrin, Bordeaux, France; 2 Institut Gustave Roussy, Villejuif, France; 3CHU Bordeaux - Hôpital Saint André, Bordeaux, France; 4CHU Bordeaux - Hôpital Haut-Lévêque, Bordeaux, France. Objective: In patients with metastatic cancer, bone metastases, frequently localized at the trochanteric region and femoral neck, cause pathological fractures with particularly serious consequences for these patients, highly vulnerable and difficult to operate. Some techniques are reported in the literature such as femoroplasty or triple screwing combined to cementoplasty. A new prevention dedicated osteosynthesis device (PDOI), made of polymer and combined with bone cement, has been developed as a minimally invasive treatment for lytic bone lesions of the proximal femur. A clinical study has been conducted to evaluate its implantation feasibility and its efficacy in strengthening this pre-fractural lesions. Methods: This clinical was a multicenter, single-arm, prospective, pilot study on a 10-patient cohort. To date all 10 patients were implanted. Tolerance of the PDOI and occurrence of hip fractures were assessed during a one year follow-up. Results: Mean age and BMI of patients were 60.0r5.3 years and 23.6r3.2 kg/m2. Mean Mirels score was 9.1 (8-12) and the EGOG Functional status was 1.3 (0-3). Mean duration of implantation were 92 (60-155) minutes. Six (6) patients were positioned supine, 4 in lateral decubitus. Mean cement quantity combined with the osteosynthesis device was 9.5 (3-15 cc). Only one case of cement leakage was reported and was resolved without complications by the removal of the excess of cement. Average hospitalization was short with 2.3 r 1.4 days. In addition, it should be noted that 4 of the 10 patients (40%) were discharged the day following the intervention, suggesting that the implantation could be performed as an ambulatory procedure. At 2 months, Visual Analog Scale (VAS) was 2.8 (2-3) and OHS-12 score was 23.5 (3-42). One oncologic patient was diagnosed at 6 months follow-up with an asymptomatic femoral neck fracture in a context of tumor progression. One patient fall was reported during the follow-up and did not have any clinical consequences. Conclusions: Results of this prospective study demonstrates the feasibility of the implantation of the PDOI with a controlled procedure thanks to a specifically developed instrumentation. This new treatment is an interesting alternative as it allows to continue radiotherapy and avoid to discontinue chemotherapy. Patients’ follow-up data are expected to confirm the efficacy of this technique, which appears to be a promising palliative technique to prevent fracture during the end of life of advanced cancer stage patients. Paper 41: A Novel Thermal Accelerant for Augmentation of Microwave Energy during Image-Guided Tumor Ablation K.C. Park1, E. Walsh3, V. Frank2, M. Primmer2, S. Collins2, D.E. Dupuy2. Diagnostic Imaging, Rhode Island Hospital / Brown Medical School, Providence, RI; 2Diagnostic Imaging, Rhode Island Hospital, Providence, RI; 3Brown University, Providence, RI. 1

Objective: The largest challenge in thermal ablation of liver tumors (e.g. hepatocellular carcinoma and CRC mets) is a relatively high recurrence rate (~30%) for which incomplete ablation at the periphery is one likely reason. To overcome this challenge, we have developed a novel thermal accelerator (TA) to demonstrate its capability to, 1) augment MW energy; 2) turn into a gel at body temperature; 3) act as a CT or US contrast.

Methods: A single MW antenna (SynchroWave ST Antenna, Perseon Medical, Salt lake City UT) was placed in a 1%(w/v) agarose phantom with the following conditions: frequency (Ȟ)= 915 MHz, power (W)= 15, 45 and 60 W and duration (t)= 5 or 10 minutes. TA was placed in parallel to the antenna at various distances (0.1, 1,1.5 and 2 cm). During heating, remote thermocouples recorded temperature changes. US was used to visualize the TA placement and CT was performed to measure density changes over several TA concentrations. Results: Figure 1. TA (100 mg/mL) was compared with other substances under the same MW conditions: 915 MHz, 15W where temperature was measured 1 mm from the antenna. Figure 2. The thermal accelerant augments the MW energy in a concentration dependant manner and reached beyond 60 oC within 5 minutes (c. 1 minute 250 mg/mL; < 3 minutes 100 mg/mL, respectively) in comparison to the sample without the thermal accelerant. Figure 3. The degree of the CT contrast is proportional to the concentration of the thermal accelerant (TA). A TA solution is CT visible: A) 1. Distilled water -15 Hounsfield (HU), 2. TA (10 mg/mL 286 HU), 3. TA (100 2056), 4. TA (1000 3070); B) the same samples in A with computer-aided enhancement. 10 mg/mL TA yields a discernible contrast comparing to water in CT. Figure 4. A whole calf liver was heated with MW energy 60 W, 915 MHz: Left) 350 PL of 100 mg/mL TA was injected to a point 1.5 cm away from the tip of the MW antenna. After 10 minutes, the area was cut open to observe the polymer solution transformed into a precipitate; Right) Temperature increase is proportional to the TA concentration. At 250 mg/mL, the temperature reached 60 oC within 3 minutes. At 100 mg/mL, it took approximately 5 minutes while the temperature increase was nominal without TA. Conclusions: We have developed a novel TA that can turn from a liquid to a gel in body and augment MW energy. Furthermore, this ‘non-toxic’ material is visible under CT or US. Thus, an accurate amount of TA can be injected to a target area (e.g., periphery of the tumor) under CT or US as image-guidance to ensure complete ablation. We are currently evaluating the ability of TA to block the “heat sink” effect, another major cause of incomplete ablation.

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level fractures were recorded. Measures from patients undergoing KIVA were compared to the vertebroplasty group. Results: 25 proven MM patients were included with a total of 42 vertebral body levels treated. 11/25 (44%) of patients (21 levels) were treated exclusively with the KIVA device and 14/25 (56%) of patients (21 levels) were treated only with vertebroplasty. In the KIVA group, mean pre-procedure BPI 6.45 r 2.5 SD decreased to 2.55 r 2.6 on post procedure follow up. Pre-procedure mean RMDQ 16.1 r 5.51 decreased to 7.57 r 7.66. In the vertebroplasty group, mean pre-procedure BPI 7.15 r 2.34 decreased to 3.82 r 2.86 on post procedure follow up. Pre-procedure mean RMDQ 16.7 r 2.41 decreased to 8.4 r 6.14. Post procedure pain medication requirements decreased in 9/11 (82%) patients in the KIVA group versus 9/14 (64%) in the vertebroplasty group. No adjacent level fractures occurred in the KIVA group. There were 2 adjacent level fractures in the vertebroplasty group. Conclusions: This is the first U.S. report of vertebral augmentation using the KIVA system in pathologic compression fractures related to MM with efficacy in pain relief and decreased medication requirements similar to that of vertebroplasty. Our series suggests that the trend toward lower incidence of adjacent level fractures seen with use of the KIVA in patients with osteoporosis may also extend to the treatment of MM patients.

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Paper 42: Combination of Electroporation and Electrolysis: A Novel Cellular-Level Tissue Ablation Modality

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M.K. Stehling1, E. Guenther2, N. Klein3, P. Mikus4, B. Rubinsky5. 1 Radiology, Institut für bildgebende Diagnostik, Offenbach am Main, Germany; 2Inter Science GmbH, Luzern, Switzerland; 3Tumor Therapy Center, Institut für bildgebende Diagnostik, Offenbach am Main, Germany; 4Inter Science GmbH, Luzern, Switzerland; 5Inter Science GmbH, Luzern, Switzerland. Objective: The combination of reversible electroporation (RE) with electrolysis is an innovative, non-thermal way to ablate tissue efficiently. The elegance of the technology lies in the permeabilization of the cell membrane within the treatment field, combined with electrolysis to electrochemically synthesize compounds that kill the affected cells, all by using the same electrodes. This combination, called E2, allows for lower necessary energies than irreversible electroporation (IRE), while at the same time it is possible to create much larger maximum ablation volumes in a gentle way, as it preserves sensitive structures that would normally be affected by other ablation modalities which use heat or freezing. Methods: E2 studies were carried out on liver, kidney, rectum, gall bladder and nerves in 9 pigs under ultrasound guidance and both with and without paralyzing anesthetics. Two probes were applied to deliver various electroporation parameters as well as different quantities of electrolysis. After harvesting and sectioning the treated organs, the tissue samples were stained with H&E and Mason’s trichromatic stain and examined histologically. Results: Reproducible uniform lesions of up to 200 cm3 during a treatment time of five minutes were created. Within the treatment field, a variety of cell death forms were produced, depending on the applied E2 protocol and the location, as different mechanisms take place at the anode and the cathode. It is possible to monitor ablation and differentiate between the two components of E2 with ultrasound: The signature of tissue affected by reversible electroporation is hypoechoic, while the effects of electrolysis pose as hyperechoic. As both electrical fields for membrane breakdown and driven diffusion for the distribution of electrolytic species can be modelled using differential equation solver, the treatment field geometry can be approximated with computer modelling. Conclusions: E2 is a novel non-thermal tissue ablation method which works on a cellular-level and makes it possible to achieve large and reproducible lesions. It has lower toxicity and is faster than electrolysis alone, while it can produce larger treatment areas compared to IRE and has lower requirements for muscle relaxation. Even though these early results require further research, the combination of RE with electrolysis is a promising new technology for tissue ablation with applications in the oncological field. Paper 43: Feasibility Assessment and Analysis of CT-Thermometry during Microwave Ablation: Early Results in Ex Vivo Porcine Kidneys and Livers J. Park1, R. Cazzato2, P. Saccomandi2, C. Massaroni2, G. Francesco2, J. Park1, E. Schena2. 1City of Hope, Duarte, CA; 2University Campus Bio-Medico di Roma, Rome, Italy. Objective: Thermometry based on Computed Tomography (CT) is emerging as a promising technique for monitoring temperature change during hyperthermal cancer treatment. The aim of the present study was to assess the feasibility of CT - based thermometry during microwave ablation (MWA) in both ex vivo porcine livers and porcine kidneys. Methods: Fresh porcine livers and kidneys were treated using two parallel microwave antennas (Certus 140, NeuWave) at 65W and for 4 minutes per ablation. Organs were scanned pre-ablation and serially at repeating intervals during MWA treatments using the following settings: kidneys (24 serial volumetric acquisitions, 10 seconds per acquisition) and livers (16 serial volumetric acquisitions, 15 seconds per acquisition). Each treatment was repeated under different CT settings (i.e., kVp and mAs). During MWA, the ablation temperatures were measured at two points with thermocouples located at different distances from the paired antennas, ranging between 10 mm and 30 mm. The relationship between the CT number (in Hounsfield Unit) and the increase of tissue temperature was obtained by using a linear regression analysis. Thermal sensitivity of the technique, showing the change of the CT number per unit of temperature increase, was modeled and estimated as the slope of the best fitting line. Results: Tissue temperature alterations during MWA were determined in both ex vivo livers and kidneys. The tissue temperature increased throughout the whole MWA, and its change was dependent upon distance from the heating source: the further the distance from the antennas, the lower the temperature increase. The CT number was determined to inversely correlate with tissue temperature in a linear relationship with thermal sensitivities of each ex vivo organ type as follows: about -0.34 HU/°C (kidney) and about 0.52 HU/°C (liver), respectively. At higher kVp and mAs, CT-thermometry performs better with respect to the measurement of thermal dispersion.

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Conclusions: CT-thermometry can be used to monitor real-time changes in tissue temperatures during hyperthermal therapies. Our early results suggest that thermometry based on serial CT imaging during MWA is technically feasible. This technique is particularly attractive because it is non-invasive and can be used to monitor three-dimensional temperature distributions in heated tissues, thereby, providing a powerful new tool to potentially monitor ablation completeness in real-time during MW or other thermal ablation procedures. Paper 44: Characterization of a Microwave Ablation Device Characteristics in a Perfused Liver Model D.T. Johnson, G.D. Dodd. Radiology, University of Colorado Denver, Centennial, CO. Objective: Ablation has become a significant treatment option in the armamentarium of interventional oncologists. With the development of new devices, precise definition of the ablation characteristics of the devices is essential for safe and effective usage. This study evaluates the ablation characteristics of the Emprint 2450 MHz (Covidien, Boulder, CO) Microwave ablation system against a well-characterized radiofrequency (RF) ablation probe (Cool-Tip, Covidien, Boulder, CO) in a perfused bovine liver model. Methods: This study was exempt from IACUC review. An in-vitro bovine liver model perfused with autologous blood via the portal vein at three flow rates (60, 80, 100 ml/min/100g liver) was utilized to evaluate the ablation characteristics of this microwave device at two different powers (45W and 100W) with a standard 10 minute ablation time compared to the recommended impedance mode for the RF probe for 12 minutes. Ultrasound was utilized to place the probes in order to stay at least 2 cm away from the liver capsule and major hepatic vessels. The analysis of the size of the lesions produced by the devices was performed by gross dissection with each lesion measured in 2 dimensions (orthogonal short axis diameter (SAD) and parallel long axis diameter (LAD) with the lesion volume calculated using the equation for an ellipsoid (V=4/3S (LAD/2) (SAD/2) (SAD/2)) and sphericity calculated using the method of Hines-Peralta. Results: Blood flow rate did not create statistically significant differences for SAD, LAD, ablation volume or sphericity for either of the devices. There were significant differences by device for ablation volume (p<0.0001), LAD (p<0.0001), SAD (p<0.0001) and sphericity (p<0.0001). The largest ablation volumes were by the Emprint 2.45 GHz device at 100W and the smallest by the Emprint 2.45 GHz device at 45W. Ablation LADs were shortest by the Emprint at 45 W. For SAD, there were significant differences between Emprint 2.45 GHz device at the 100W compared to both the 45W setting (p<0.0001) and to Cool-Tip (p<0.0001); ablation SADs were shortest, and similar, for the Emprint 2.45 GHz device at 45W and Cool-Tip. The sphericity of ablation was significantly (p<0.0001) better for the for the microwave probe at both powers levels than the RF probe. Conclusions: The Emprint microwave device demonstrates consistent ablations sizes, unaffected by flow rate, which are consistently spherical at both 45 and 100 W. The sphericity is significantly greater with the Emprint than the RF ablation probe. Improved sphericity and consistent ablation sizes would be expected to improve ablation safety and efficacy of liver tumor treatment. Paper 45: CT Imaging Measurements Predict Gross Ablation Size at 48 Hours Following Microwave Ablation of Swine Lung H. Kodama1, E. Ueshima1, S. Gao1, K. Howk2, S.B. Solomon1, G. Srimathveeravalli1. 1Memorial Sloan-Kettering Cancer Center, New York, NY; 2Medtronic, Minneapolis, MN. Objective: Desiccation of tissue during microwave ablation and its subsequent recovery can alter imaging appearance of the ablation zone over time. The purpose of our study was to define CT appearance of ablation zone evolution following microwave ablation of swine lung in the sub-acute setting, and determine whether CT measurements performed 48 hours post-treatment can predict size of underlying ablation. Methods: Ten percutaneous microwave (Emprint, Medtronic, Minneapolis, MN) unilateral lung ablations were performed in 4 swine (2-3 ablations/animal). All sites were treated at 2540 MHz and 100 Watts, for either 2 minutes (low; 6 ablations) or 10 minutes (high; 4 ablations, at least one/animal). Non-contrast and dual-phase (30 seconds and 90 seconds) contrast enhanced CT images were obtained at immediate post-treatment and at 48 hours, just prior to sacrifice. Lungs and trachea were removed en-bloc after euthanasia and were perfused with formalin for fixation. Fixed lungs were step sectioned at 3-5mm thickness and photographs of the ablation zones were taken. Measurements were aggregated as mean r standard deviation, comparisons were performed using Student’s T-test and p<0.05 was considered statistically significant. Results: Immediate post-ablation volume measured on CT was smaller in both treatment groups (high: 11.5r1.7 cm3; low: 2.9r1.4 cm3) than measurements at 48 hours (high: 14.3r3.3 cm3; low: 4.4r1.7 cm3), p<0.05. Two-axis measurements

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performed on the largest ablation cross section on CT at 48 hours corresponded well with gross ablation measurements for both high (CT: 3.5r0.5x2.4r0.3 cm vs. Gross: 3.3r0.6x2.1r0.2 cm; no statistical difference) and low (CT: 2.3r0.5x1.5r0.3 cm vs. Gross: 1.9r0.5 1.3r0.3 cm; no statistical difference) dose ablations. Conclusions: Volume of microwave ablation in the lung changes substantially in the sub-acute setting, and CT measurements performed at 48 hours closely matched gross ablation size. Co-registration of pre-treatment tumor and immediate post-procedure ablation volume may be required to ensure accurate measurement of ablation margins during MWA of lung tumors in patients. Paper 46: Endoluminal RFA and Stenting - The Novel Technique of Inoperable Malignant Biliary and Pancreatic Duct Stricture Percutaneous Management

Objective: Malignant stricture recanalization percutaneous technique is presented Methods: 147 procedures were attempted to 127 patients with unresectable tumour induced biliary block; among them - cholangiocarcinoma 46, pancreatic cancer 32, liver metastatic invasion 26, gallbladder cancer 8, papilla of Vater tumor 8, hepatocellular carcinoma 7.7 patients with pancreatic head inoperable cancer with recently manifested pancreatitis and/or hyperglycemia underwent tumour blocked PD segment recanalisation attempt by RF processing. Patients underwent the procedure after preliminarily performed percutaneous biliary or PD drainage. The first step is the wire manipulation by 5 Fr guiding catheter across the strictured duct segment. The RF ablation catheter then was inserted over a guide wire via introducer sheath for ablation of the tumour tissue. RF catheter delivered 15 W over a 2-min period for each application. The RF energy was applied in a sequential manner along the full length of the malignant stricture under fluoroscopic guidance. Procedure was finished by balloon ductoplasty in the first 10 biliary cases and by self expanding or balloon mounted metal stent implantation in the rest biliary (8-10 mm stent) and all PD (5-6mm stent) cases. Procedure is completed by the safety drainage catheter reposition. Results: Biliary procedure technical succes rate was 98.7%, resulting in general condition improvement; in 2 (1.3%) cases the guidewire conduction failed; Biliary stent occlusion was documented in 14 (11.0%) of 127 biliary patients in 3 weeks to 8 months after RFA&stenting, requiring percutaneous drainage. in PD cases the procedure was completed in 6 (85.7%) cases, being impossible because of guidewire conduction failure in 1 (14.3%) case; two patients with uncontrolled diabetes had dramatic improvement in blood sugar control. Stent patency problem due to tumor ingrowth in 11 months after recanalization was detected in one case. There was no 30 day mortality, hemorrhage or pancreatitis documented. Conclusions: Percutaneous endoluminal RFA&stenting is safe and effective in biliary and PD duct block recanalization; it should be routinely suggested as a possible treatment option of inoperable biliary and PD stricture cases

Contrast injection via percutaneously positioned drainage catheter opacifies the pancreatic duct, showing tumor induced stricture

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M. Mizandari1, N. Habib2, T. Azrumelashvili3. 1Tbilisi State Medical University, Tbilisi, Georgia; 2Surgery and Oncology, Imperial College London, London, United Kingdom; 3Tbilisi State Medical University, Tbilisi, Georgia.

Contrast injection after RFA&stenting shows the PD complete recanalization Poster 1: Predictors of Lung Shunt Fraction and Feasibility of Selective Internal Radiation Therapy without 99mTc-Macroaggregated Albumin Injection A.C. Gupta1, R.K. Gurajala1, J. Bullen2, K. Karuppasamy1. 1Radiology, Cleveland Clinic Foundation, Cleveland, OH; 2Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH. Objective: To study the correlation between patient factors, tumor type and imaging based variables to the lung shunt fraction (LSF) measured after 99mTc-macroaggregated albumin (TcMAA) injection in patients being considered for Yttrium-90 based selective internal radiation therapy (SIRT) and to evaluate the feasibility of SIRT without TcMAA injection. Methods: Between February 2012 and April 2015, 60 patients [46 male, mean age: 63 (12) years] underwent planning hepatic angiogram and LSF was measured following intra-arterial injection of TcMAA. The tumor type was categorized as follows: primary liver cancer, colorectal metastases to the liver, and other metastases to the liver. CT/MRI performed immediately prior to the angiogram (mean interval 44 days; range: 0 to 176 days) was used for analysis. There were no patients with hepatic vein thrombus. Single-predictor linear regression models were used to individually assess seven potential predictors of LSF: age, sex, tumor type, number of lesions, size of largest lesion, cumulative size of all lesions, and portal vein (PV) thrombus (presence vs. absence). Predictors significant at the 0.05 level were then included simultaneously in a model of LSF. The radiation dose prescription for a hypothetical scenario is estimated using TheraSphere Treatment Window Illustrator. Results: Two of seven potential predictors showed a statistically significant association with LSF: tumor type (colorectal metastasis vs. all other type) and cumulative size of all lesions. Each 1 cm increase in the cumulative size of all lesions was associated with an increase in LSF of 0.18 (p=0.044). Patients with colorectal metastases had higher LSF (mean: 7.5, sd: 7.0, n=12) compared to patients with primary liver cancer or other metastases (mean: 4.9, sd: 2.8, n=48) (p=0.043). When these two variables were included simultaneously in a model of LSF, the estimated effect sizes remained similar to single-predictor models, though the p-values increased slightly (p=0.054 and 0.054 respectively). The mean LSF was 5.4% (SD 4.0; range 1.3-26.9). 98% of LSF were less than 15%; at this presumed lung shunt fraction, an SIRT dose of 120 Gy to 1000 cc of liver would result in 22 Gy to the lungs. Radiation delivered using 1 Gq of TheraSphere per 100cc of liver on a predetermined weekday would range from 137 Gy to 117 Gy based on 0 to 15% lung shunt fraction (1% waste is assumed). Conclusions: In vast majority of patients, LSF measured using TcMAA injection is <15%. The type of hepatic tumor and the cumulative size of all the lesions appear to be independently related to the LSF. Hence, in selected group of patients, single-session SIRT without TcMAA injection might be safe and adequate using a pre-arranged patient specific radiation dose. A prospective controlled study is required to assess the safety and adequacy of such a treatment plan.

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* Multiple-predictor model included tumor type (colorectal metastases vs. all other diagnoses) and the cumulative size of all lesions simultaneously. Poster 2: Improved Stability of Lipiodol-Drug Emulsion for Transarterial Chemoembolisation of Hepatocellular Carcinoma Results in Improved Pharmacokinetic Profile: Proof of Concept using Idarubicin B. Guiu1, A. Schmitt2, M. Pierredon1, V. Schembri1, M. Boulin2. 1 Radiology, St-Eloi University Hospital - Montpellier, FRANCE, Montpellier, France; 2CHU Dijon, Dijon, France. Objective: To investigate the relationship between the improved stability of the anticancer drug-lipiodol emulsion and pharmacokinetic (PK) profile for transarterial chemoembolisation (TACE) of hepatocellular carcinoma (HCC). Methods: The stability of four doxorubicin- or idarubicin-lipiodol emulsions was evaluated over 7 days. Clinical and PK data were recorded after TACE with the most stable emulsion in eight unresectable HCC patients. Results: The idarubicin-lipiodol (1:2 v:v) emulsion was the most stable with no phase separation at 5 days whereas complete phase separation for the doxorubicin-lipiodol emulsions was observed between 4 and 12 hours. Two months after TACE, 1 complete response, 5 partial responses, 1 stabilisation, and 1 progression were observed with two asymptomatic grade 4 biological adverse events. The most frequent grade 3 TACE-related adverse events were pain and biological abnormalities. Mean idarubicin Cmax and AUC0-24h were 12.5 r 9.4 ng/mL and 52 r 16 ng/mL.h. Most of the plasma exposure occurred over the 24 hours after the TACE procedure (76% of the estimated total AUC [68 r 23 ng/mL.h]). The estimated mean bioavailability of idarubicin was 40%, meaning that 60% of idarubicin remained in the liver. Conclusions: This study demonstrated that improved stability of drug-lipiodol emulsion results in improved PK profile after TACE of HCC. Encouraging data for safety and responses support further clinical studies with the idarubicin-lipiodol (1:2 v:v) emulsion in this indication. Poster 3: Minimally Invasive Techniques for Pain Palliation in Metastatic Bone Disease: An Extra Step in the Analgesic Ladder D. Filippiadis, A. Mazioti, S. Spiliopoulos, C. Kostantos, E. Brountzos, N. Kelekis, A. Kelekis. 2nd Department of Radiology, University General Hospital “ATTIKON”, ATHENS, Greece. Objective: To illustrate different Interventional Radiology techniques for pain palliationTo learn about proper patient selection and therapeutic algorithmsTo learn about protective techniques which increase safety of palliative therapies Methods: Pain pathophysiology in metastatic bone disease includes tumor driven osteolysis and microfractures, chronic neuronal stimulation with altered neurotransmitter express and neuropathic pain. Therapeutic armamentarium includes conservative medical therapy, surgical options, radiation therapy, Interventional radiology techniques such as neurolysis, embolization, ablation and bone augmentation. Results: Percutaneous neurolysis can be either chemical (by means of phenol or alcohol) or thermal (using radiofrequency or cryoablation). Bone augmentation techniques apply in the spine or peripheral skeleton and include injection of PMMA either solely performed or combined to introduction of implants (screws, metallic mesh of microwires/needles, peek cages, stents etc). Bone ablation provides simultaneous treatment of both the source and sensation of pain as well as tumor decompression and inhibition of osteoclast activity. Conclusions: Pain is a common symptom in metastatic bone disease not adequately treated in the majority of cases. Interventional Radiology techniques with proper patient selection provide attractive, efficient and safe alternatives for pain palliation in oncologic patients.

Interventional Radiology techniques provide safe and efficacious solutions for pain reduction in metastatic bone disease; these techniques could be included in the 4th step of WHO analgesic ladder Poster 4: Non-Biologic Injectable Tumor Mimic for Hepatic Ablation A. Smolock1, M.M. Cristescu1, G. Carberry2, M. Klapperich1, C. Brace1, F. Lee1. 1University of Wisconsin, Madison, WI; 2University of Wisconsin--Madison, Madison, WI. Objective: In our efforts to simulate and evaluate ablation zone properties in the laboratory setting, we sought to create a robust non-biologic liver tumor phantom model for use in ablation modeling and pre-clinical testing. The most desirable model would be 1) injectable into both in vivo and ex-vivo animal tissue, 2) visible on CT, US, & gross examination, 3) inexpensive, and 4) easy to create. Our objectives are to give the reader a step-by-step guide to preparation of this model, detail pearls and pitfalls to its creation, and describe its potential uses from our experience. Methods: An injectable non-biologic gel model was selected based on its physical properties and probability of meeting our criteria. Using data from a handful of reports of such models in the literature, we began to develop and test an injectable, methylene-blue stained agarose, cellulose, and glycerol-based solution. The mimic was injected into in vivo and ex-vivo porcine and ex-vivo bovine liver under various conditions with using varying 1) tissue temperatures, 2) material composition, 3) ultrasound (US) and CT-fuoroscopy guidance techniques for injection/imaging, and 4) size and type of injection systems. Results: Our experience yielded an injectable non-biologic hepatic tumor mimic which met all of our above criteria. We used a 200 mL mixture detailed in other reports composed of 6 g agarose, 6 g cellulose, and 14 mL glycerol mixed into water, heated for 5 minutes to 95 degrees C. We additionally agitated the mixture and added 10 mg methylene blue stain to increase visibility. This tumor mixture is liquid at high temperatures (> 60°C), allowing for syringe injection through an 18-gauge (or larger) needle. The gel subsequently congeals at body temperature. Slow injection into pliable porcine liver forms a 0.5-2.0 cm well-circumscribed lesions which retain their ovoid shape despite hepatic deformation or ablation. The mimic is hyperechoic on US and hypodense on noncontrast and contrast-enhanced CT, allowing easy differentiation from normal or ablated hepatic parenchyma (Image top). Additionally, the methylene blue-stained tumor is easily differentiated from both normal and ablated liver on gross evaluation (Image bottom). Conclusions: The creation of an injectable in vivo and ex-vivo porcine hepatic tumor phantom which is visible on CT, ultrasound, and gross pathology is possible using a relatively simple, inexpensive, and reproducible technique. This phantom allows for bench research of ablation zone margins and other parameters requiring the presence of a tumor phantom.

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cell lines (p<0.01); Figure 1A. SW43-DOX EC50 concentrations (PM; (95%CI)) were significantly lower compared to the individual components (SW43-DOX vs. unconjugated SW43 + Doxorubicin/SW43/Doxorubicin): MDA-MB-231: 4.8 (4.7-4.8) vs. 12.83 (11.85-13.9)/ 12.73 (12.15-13.35)/ 121.5 (107.2-137.8); p<0.001. MCF-7: 12.42 (11.32-13.63) vs. 18.46 (16.85-20.22)/ 28.6 (25.83-31.67)/ 136.1 (117.7-157.4); p<0.001; Figure 1B. Conclusions: The novel targeted drug SW43-DOX binds to the V2-receptor with high affinity, internalizes into the cancer cells specifically and exerts a superior antitumoral effect against breast cancer cells compared to the non conjugated drug (SW43 + Doxorubicin), SW43 or Doxorubicin in vitro. SW43-DOX may be a potential targeted drug for systemic breast cancer treatment and for drug-eluting bead transarterial chemoembolization of liver metastases.

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Top. Greyscale ultrasound image demonstrates tumor mimic appearance post-injection within ex-vivo porcine liver. Post-ablation CT image demonstrates the very low attenuation tumor mimic (black arrow) within a portion of the hypodense ablation zone (white arrow). Bottom. Gross cross-section through an ablated tumor mimic (black arrowhead) demonstrates the methylene-blue stained tumor phantom within the pale white ablation zone (white arrowhead), surrounded by normal hepatic parenchyma. Poster 5: SW43-DOX - A Potential New Targeted Drug for the Treatment of Breast Cancer Liver Metastases - An In Vitro Evaluation of Receptor Binding Affinity, Tumor Internalization and Anticancer Effect 1

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J.M. Ludwig , Y. Gai , L. Sun , D. Zeng , K. Kim . Division of Interventional Radiology, Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT; 2Molecular Imaging Laboratory, Department of Radiology, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA. Objective: The V2-receptor is overexpressed on many cancer cells including breast cancer representing an attractive target for tumor therapy. We developed and synthesized SW43-DOX, a drug conjugate consisting of the cancer toxic V2-receptor agonist SW43 and the anti-cancer drug Doxorubicin (DOX). We have shown that SW43-DOX can be loaded onto and eluted from drug-eluting bead particles. Here, we evaluated the binding affinity of SW43-DOX to the V2-receptor, quantified the specific internalization and assessed the anticancer potential in vitro. Methods: The human breast cancer cell lines MDA-MB-231 & MCF-7 were tested. The chelator L-NETA was attached and loaded with Lu177 for saturation binding (SBA) & internalization assays (IA). SBA: V2-receptor blocking was achieved with 10-100 PM SW43 for 15 min. at RT prior to incubation with 1-300 nM SW43-DOX-Lu177 in HBSS buffer + 0.1% BSA (3.5h, 4°C). IA: The receptor was pre-blocked (7.5 PM SW43; 15 min. at RT) & cells were incubated with 75 nM SW43-DOX-Lu177 for 0.5, 1, 2h at 37°C/5% CO2. The cell surface bound fraction was removed with HBSS +20 mM NaOAc; pH4.0 (10 min; 37°C/5% CO2). Cells were harvest with 0.5% SDS, radioactivity measured (Cobra Gamma-counter, Packard Bell) & normalized to whole cell protein. The half maximal effective concentration (EC50) was assessed by treatment with SW43-DOX and its components ranging from 1-400 PM (CellTiter-Glo®; Promega). Statistics: IA: ANOVA + Bonferroni post-hoc test. SBA: Normalized one site saturation non-linear regression fit model with calculation of the dissociation constant (KD) and maximal binding capacity (Bmax). EC50: Dose response non-linear fitting model; Extra Sum-of-Squares F Test. Prism V6.0. Results: SW43-DOX specifically binds to the V2-receptor with high affinity: KD (nM; rstandard error) for MDA-MB-231 was 21.46 r15.9 and 48.1 r20.0 for MCF-7 cells. The maximal specific cell surface binding capacity Bmax (pmol/mg protein; rstandard error) for MDA-MB-231 cells was 42.9 r7.9 and 82.1 r12.4 for MCF-7 cells. There was significant specific internalization at all time points for both

Figure 1: A) SW43-DOX internalization kinetics and B) Dose dependent viability comparison after 24h in vitro treatment. Error bars: Mean rstandard error; nt3. Poster 6: The Role of Immunotherapy in Interventional Oncology A. Ghodadra1, K. Kim2. 1Radiology, UPMC, Pittsburgh, PA; 2Radiology, Yale, New Haven, CT. Objective: The objective of this exhibit is to review the types of immunotherapy, their applications to interventional oncology (IO), and the current evidence supporting the use of immunotherapy in IO. Methods: Immunotherapy refers to the use of treatment that seeks to recruit patients’ immune systems in order to target cancer. Recently, there has been an increasing interest in the use of immunotherapy in IO. For example, percutaneous cryoablation has been shown to elicit a local immune response and there is growing evidence that combination immunotherapy and cryoablation could yield improved therapeutic efficacy as well as. Furthermore, there is growing evidence that the combination of immunotherapy with radiation therapy also may result in improved therapeutic efficacy. Results: A review of the mechanisms of immunotherapy will be presented. Additionally, the immune effects of traditional interventional oncology treatment techniques will be discussed. An overview of targets for immunotherapy in interventional oncology will be presented. The state of the current literature regarding immunotherapy in IO will also be discussed. For example, the mechanism and role of PD-1 and PD-1L in immunotherapy and its impact in IO will be presented. Finally, how these immunotherapies could be combined with locoregional therapy (LRT) for targeted immunotherapy IO is also discussed in addition to the future studies needed. Conclusions: This review will provide the reader an overview of the opportunities for enhancement cancer treatment offered by immunotherapy in IO. The immune effects of current treatments in IO along with means of recruiting the immune system are discussed in this review. Poster 7: Assessment of Folate Receptor and Glial Fibrillary Actin Protein Expression in Hepatocellular Carcinoma vs. Normal Liver Tissue M.S. Al-Natour1, D. Das1, N. Koirala2, A. Rai1, G. McLennan3. Interventional Radiology, Cleveland Clinic, Rocky River, OH; 2Chemical and Biomedical Engineering, Cleveland State University, Cleveland, OH; 3 Interventional Radiology, Cleveland Clinic, Cleveland, OH. 1

Objective: Folate receptor (FR) is known to be overexpressed in many different types of cancer including hepatocellular carcinoma (HCC). Hepatic stellate cells (HSC) are the vitamin A storing cells residing in the space of Disse in normal liver,

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which in response to injury gets activated into myofibroblast leading to scar tissue formation and extracellular matrix remodeling. In the liver, glial fibrillary actin protein (GFAP) is expressed only by the HSCs. From the available human tissue (tumor and normal) samples we aim to verify the presence of FR in human HCC and compare it to normal liver. In addition we aim to compare the distribution of HSC between normal liver and HCC. Methods: Frozen sections of explanted livers from 4 patients with known HCC who underwent liver transplant without any prior therapy were stained for the presence of FR and GFAP. A similar approach was done with frozen sections of explanted livers of 3 patients without known history of hepatic cirrhosis or hepatocellular carcinoma. After processing the liver specimens, they were confirmed to be free from gross necrosis & thus analyzable. Tissue sections were fixed with pre-chilled acetone (-20 C), following which they were washed with 1X PBS and incubated in 0.3% H2O2 solution for 10 min at room temperature to block endogenous peroxidase activity. Sections were then washed and blocked with 10% normal goat serum and incubated with FR and GFAP primary antibody, overnight at 4 C. Slides were washed after the incubation with 1XPBS followed by incubation with the required secondary antibody (secondary anti-rabbit in this case). Using Vectastain Elite kit and AEC chromogen substrate, slides were developed followed by counterstaining the nuclei with Gill’s hematoxylin. Excess hematoxylin was washed with tap water. Intense red stain on the sections is indicative of the presence of the target protein in the tissue while nuclei appear to be blue. Results: FR overexpression was detected in all HCC samples. GFAP overexpression was detected in all HCC samples. Only one normal pre-labeled sample showed increased GFAP and low FR, indicative of the tissue being in early fibrosis/cirrhosis and mislabeling as normal. Conclusions: These findings support the feasibility of novel folate receptor targeted therapy of hepatocellular carcinoma and confirms the link between hepatic cirrhosis and hepatocellular carcinoma. Weather targeting GFAP to decrease hepatic fibrosis can reduce the risk for developing hepatocellular carcinoma remains questionable and it is worthy to further investigation.

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The tumors in the bladder were fed by blood flow from the both sides with different emphasis (arrow)

Super-selective arterial DSA indicated both superior vesical artery and inferior artery were supplying the tumor within the bladder (arrow) Poster 9: Thermal Ablation of Suspicious Renal Masses: Is a Biopsy Necessary? A.W. Maxwell1, M. Tsang Mui Chung1, G. Baird1, L. Wang2, D.E. Dupuy1. 1 Department of Diagnostic Imaging, The Warren Alpert Medical School of Brown University, Providence, RI; 2Department of Pathology, The Warren Alpert Medical School of Brown University, Providence, RI. Poster 8: Outcomes of Arterial Chemotherapy and Chemoembolization for Invasive Bladder Urothelial Carcinoma X. An. Shanghai First People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China. Objective: To evaluate efficacy of internal iliac arterial interventional chemotherapy and embolization for invasive bladder urothelial carcinoma. Methods: 49 cases of invasive bladder cancer were recruited, including 30 patients with serious hematuria after ineffective conservative therapy. Except 16 patients who did not want surgery, the others could not tolerate radical cystectomy because of accompanying with severe heart or lung diseases. After bilateral transcatheter cisplatin&epirubicin--based combination chemotherapy, superior and/or inferior vesical arteries supplying tumors were embolized by LipiodolR emulsion or Polyvinyl Alcohol (PVA). Average interval time was 1.5 months and mean number of digital subtraction angiography (DSA) procedure was 5 times. Results: Hematuria ceased in all patients including one centenarian one week later. Long term effects were not as good as short. Complete response in 6 and partial response in 21 patients were achieved. The one, three and five year survival rates were 93.88%, 81.63% and 53.06%, respectively. Conclusions: Interventional chemoembolization is a safe and feasible treatment for inoperable patients diagnosed as invasive bladder cancer, especially complained about persistent hematuria. This therapeutics is a fast, effective and bladder-preserving approach, rather than palliative treatment. Embolic agents are suggested to administer if angiography show extravasation of contrast or abundance of tumor blood vessels.

Objective: To evaluate the diagnostic performance of image-guided percutaneous core needle biopsy in patients undergoing thermal ablation of suspicious renal masses, and to clarify its effect on post-ablation patient management. Methods: A single-institution retrospective chart review was performed to identify patients referred for ablation of suspicious renal masses who underwent image-guided core needle biopsy prior to or contemporaneous with image-guided thermal ablation. Biopsies were categorized according to tumor size, diagnosis and diagnostic yield, malignancy/benignity, complications, patient characteristics, and technical elements such as needle gauge and number of needle passes made. Following this, biopsy results were further classified according to the need for radiologic and/or clinical follow-up in the post-ablation period on the basis of final pathology: all malignant lesions, oncocytic neoplasms, and non-diagnostic biopsies required routine post-ablation imaging and/or clinical follow-up, while angiomyolipomas and all other definitively benign lesions did not. Results: A representative sample composed of 270 consecutive biopsies performed between October, 2000 and March, 2015 was utilized for analysis (174 males, 96 females, mean age 73 years [CI95% 71.5-74], range 32-93 years). The average maximum diameter of biopsied lesions was 2.5 cm (CI95% 2.4-2.7 cm). The median needle gauge was 20G, and both the median and modal number of passes was two [range 1-6]. One hundred forty-four (53.3%) biopsies were performed concomitantly with thermal ablation, and the median time between biopsy and ablation was 34 days (CI95% 40-61 days). A total of 52 (19.3%) patients had prior nephrectomy (15 partial, 37 total), and the mean pre-procedural creatinine was 1.3 mg/dL (CI95% 1.2-1.5 mg/dL). Minor complications occurred in 34 (12.6%) patients, of which the

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greater frequency with cryoablation (3%) versus microwave ablation (0%). Minor complications also occurred with greater frequency with cryoablation (18%) versus microwave ablation (6%). Conclusions: Percutaneous renal cryoablation and microwave ablation offer similar efficacy in the treatment of small renal masses. Local recurrence occurs with similar frequency irrespective of treatment modality. Complications appeared higher for cryoablation, although most were classified as minor. Results

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most common was perinephric hematoma (11 patients, 29.4%). There were no major complications. No instances of tumor seeding along the biopsy tract were observed. Percutaneous core needle biopsy provided an actionable pathologic diagnosis in 254 (94.1%) cases; 16 (5.9%) biopsies were non-diagnostic. The most common diagnosis was renal cell carcinoma, clear cell variant (135, 50.0%). Of those with a diagnostic biopsy, 224 (88.2%) cases were classified as malignant, while 30 (11.8%) were benign. Post-ablation follow-up was deemed necessary in 257 (97.4%) cases based on the aforementioned criteria. Conclusions: Image-guided percutaneous core needle biopsy of suspicious renal masses has a high diagnostic yield and is associated with low morbidity. The majority of biopsied lesions in our series were malignant, and nearly all patients required follow-up imaging. These results suggest that post-ablation management is infrequently affected by biopsy results, and biopsy can be safely avoided in most clinical settings. Further anaylsis is ongoing to determine the cost-effectiveness of this recommendation.

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Poster 10: Risk of Hemorrhage Related to Percutaneous Cryoablation for Renal Tumors B. Kakarala1, C. Frangakis2, C. Georgiades1. 1Interventional Radiology, Johns Hopkins University, Baltimore MD; 2School of Public Health, Johns Hopkins UNIVERSITY, Baltimore, MD. Objective: Study objective was to establish the exact risk of cryoablation-related hemorrhage during renal tumor cryoablation. Its lack of coagulative effect, compared to RFA or MWA, led to the untested assumption that cryoablation is associated with a higher risk of hemorrhage. Methods: The IRB approved this prospective study which included 261 cryoablations of renal tumors over a 7-year period. All ablations were under conscious sedation and CT guidance with a pre- and post-ablation CT. Hemorrhagic complications were recorded according to CTCAE criteria. Age, gender, tumor size, histology and number of probes were correlated with risk based on averages or proportions using their exact permutation distribution. “High-risk” subgroups were defined and tested for each variable alone, and for all combinations of variable threshold values. Lastly, we compared the subgroup with the best PPV using one variable, with the subgroup with the best PPV using all variables using the McNemmar test. Results: The hemorrhagic complication rate was 3.5%. Four patients required transfusions, 2 emergent angiograms, one both and 2 bladder irrigation for outlet obstruction. Peri-renal space hemorrhage was more clinically significant than hemorrhage elsewhere. Univariate risks were tumor size>2cm, number of probes>2 and malignant histology (P=0.005, 0.002 and 0.033, respectively). Multivariate analysis showed that patients >55 years with malignant tumors >2cm requiring 2 or more probes yielded the highest PPV (7.5%). Conclusions: Percutaneous cryoablation has a 3.5% risk of significant hemorrhage, similar to that reported for other types of renal ablative modalities, despite its lack of coagulative effect. Though older patients (>55 y.o.) with larger (>2 cm), malignant tumors have an increased risk of hemorrhagic complications, the low PPV does not support the routine use of embolization.

Poster 12: Novel Technique for Pre-Operative Removal of Intracardiac Thrombus Prior to Radical Nephrectomy and IVC Thrombectomy J. Humphrey, D.A. Palmer, T. Piemonte, J.A. Libertino. Urology, Lahey Clinic Medical Center, Wellesley, MA. Objective: Patients with intracardiac extension of inferior vena caval thrombus from renal cell carcinoma represent a difficult population for surgical planning. Here we present a case in which the thrombus is removed percutaneously via transvenous mechanical thrombectomy to the level of the renal vein ostium. Methods: A patient with stage T3c renal cell carcinoma with thrombus extension into the right ventricle developed pre-operative pulmonary emboli to the right lung, precluding safe use of cardiopulmonary bypass for surgical removal. In order to down-stage the tumor by removing the thrombus, the patient underwent transvenous mechanical thrombectomy. The patient was placed on extracorporeal membrane oxygenation, and access gained via right internal jugular vein. The thrombus was then removed from the lead point within the right ventricle. Results: Post-procedure cavogram demonstrated removal of the thrombus to the level of the renal vein ostium, effectively downstaging the tumor to T3b. The patient was then able to safely undergo radical nephrectomy with IVC thrombectomy without the use of cardiopulmonary bypass.

Poster 11: Safety and Efficacy of Percutaneous Renal Ablation: Comparison of Cryoablation and Microwave Ablation

Poster 13: Overall Survival after Image Guided Thermal Ablation of Pathologically Proven T1a RCC in Cancer Survivors

J.J. Zechlinski1, S. Dybul1, E. Hohenwalter1, S.B. White1, W. Rilling1, P. Langenstroer3, D. Filippiadis2, A. Kelekis2, S. Tutton1. 1Department of Radiology, Medical College of Wisconsin, Milwaukee, WI; 22nd Department of Radiology Dpt, University General Hospital “ATTIKON”, Athens, Greece; 3Department of Urology, Medical College of Wisconsin, Milwaukee, WI.

M.E. Abdelsalam1, S.H. Sabir1, S. Kusin1, C.G. Wood2, S. Matin2, J.A. Karam2, K. Ahrar1. 1Interventional Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX; 2Urology, The University of Texas MD Anderson Cancer Center, Houston, TX.

Objective: Small, incidental renal masses require a thoughtful treatment strategy which preserves renal function and minimizes procedural morbidity. Percutaneous ablation is an expanding, minimally invasive approach. Ablative modalities vary across institutions. Therefore, the purpose of this study is to compare the safety and efficacy of cryoablation and microwave ablation across institutions. Methods: After IRB approval, we performed a retrospective review of patients undergoing percutaneous cryoablation with a similar cohort undergoing microwave ablation for small renal masses at two institutions. Patient demographics, tumor characteristics, ablation technique, complications, and pattern of recurrence were evaluated. Results: Cryoablation was performed in 126 patients, and microwave ablation in 32. Technical success of 98% and 97% were achieved for cryoablation and microwave ablation, respectfully. Lesions were on average larger in the microwave ablation cohort (Table). Local recurrence of 9% was observed in both treatment groups. Recurrences occurred early after ablation (within 12 months) and delayed (beyond 12 months) with similar frequency (Table). Major complications occurred with

Objective: Although surgical excision remains the gold standard treatment for renal cell carcinoma (RCC), active surveillance and thermal ablation provide alternative options for patients at higher surgical risk. The purpose of our study is to investigate the effectiveness of image guided thermal ablation for pathologically proven T1a RCC in patients with other non-renal primary malignancies Methods: We performed a retrospective review of our renal tumor ablation registry for the period of January 2005 to December 2013. We included patients with T1a renal tumors (< 4 cm). We excluded patients without histologically proven RCC, those with Von Hippel Lindau syndrome, and those with prior history of RCC. Two groups were created; (A) patients with RCC and history of other non-renal primary malignancy (in remission or active), (B) Patients with RCC only. Statistical analysis was performed to compare the two groups using Fisher’s exact and Kruskal-Wallis test for demographics (age, sex) and clinical characteristics (prior or current cancer history, renal tumor Size, and complications). Overall survival (OS) was estimated using the Kaplan-Meier product-limit estimator and we conducted a log-rank test to compare the two groups. OS was measured from the procedure date to the date of last contact or death.

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Results: Seventy four patients were included in the study, 37 patients (50%) has other non-renal primary. The average age at procedure was 68.8 years. There was no difference in age (68.6 vs. 68.9; p = 0.842), sex (15 women and 22 men vs. 13 men and 24 women; p = 0.811), or tumor size (2.3 vs. 2.5; p = 0.107). Complication rates did not differ between the groups (2.9 vs. 5.9; p = 0.614). Median survival time for the entire population was 8.39 years. The probability of 5-yr (10-yr) survival was 0.74 (0.48). There was no difference in survival between the two groups (p = 0.384). Conclusions: Minimally invasive therapy with image guided thermal ablation provides safe and effective treatment for T1a RCC in patients with other non-renal malignancies. In our study, Primary malignancies or their therapy did not have discernible impact on the thermal ablation effectiveness, complications, or overall survival rates.

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Poster 14: Comparison of Percutaneous Microwave Ablation, Cryoablation and Surgery for Treatment of Sporadic RCC d4cm J.L. Hinshaw1, S. Best2, S.A. Wells3, M. Lubner4, F. Lee6, S. Nakada2, T. Wittman2, E.J. Abel5. 1Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI; 2University of Wisconsin School of Medicine and Public Health, Madison, WI; 3University of Wisconsin School of Medicine and Public Health, Madison, WI; 4 University of Wisconsin School of Medicine and Public Health, Madison, WI; 5University of Wisconsin School of Medicine and Public Health, Madison, WI; 6University of Wisconsin School of Medicine and Public Health, Madison, WI. Objective: While surgery remains the preferred treatment for small renal cell cancers (RCC) in most patients, this is in evolution and percutaneous ablative techniques are an increasingly appealing and, in some cases, preferred option in these patients. The objective of this study was to compare local tumor progression (LTP)and metastatic recurrence rates for patients treated with percutaneous cryoablation (CA), microwave ablation (MWA) or surgery for RCC d 4cm. Methods: Patient data was reviewed for all patients treated at our institution for pathologically confirmed RCC d 4cm with percutaneous thermal ablation or surgery from 2001-2015. Patients with prior history of RCC or associated syndromes were excluded. Outcome measures included local tumor progression (LTP) and metastatic disease recurrence. Fischer’s exact or chi-square tests were used to define differences between groups. Results: A total of 546 patients were included in the study. The treatments included were: 182 (33.4%) partial nephrectomies (PN), 177 (32.4%) radical nephrectomies (RN), 110 (20.1%) MWA and 77 (14.1%) CA. Age and Charlson Cormorbidity Index (CCI) were significantly higher in patients treated with ablation (p<0.001, p<0.001), while tumor grade was significantly higher in patients treated with surgery (p=0.005). There was no significant difference in RENAL nephrometry score, RCC subtype, or tumor diameter among groups (p=0.46, 0.51, 0.17 respectively). Median follow-up interval (IQR) was longer for surgery and CA compared to MWA; PN 29.3 mo (13.7-75.0), RN 41 mo (13.5-74.8), CA 37.4 mo (17.8-57.1) vs. MWA 13.8 mo (6.321.6) (p<0.001). LTP occurred in 1/182 (0.5%) RN, 0/177 (0%) PN, 8/77 (10.4%) CA, and 1/120 (0.9%) MWA patients (p<0.001). Metastatic recurrence occurred in 5/182 (2.7%) RN, 9/177 (5.1%) PN, 1/77 (1.2%) CA, and 0/120 (0%) MWA patients (p=0.38). Overall (local and distant) recurrence rate for surgery was significantly lower compared to CA was 3.6% vs 11.7% (p=0.0016), but not MWA (0/9%). The median time to recurrence for surgery was 26.8 months and 16.3 months for CA. Conclusions: Although there are biases related to tumor grade, follow up interval, and underlying comorbidities, this study suggests that CA is associated with higher LTP rates than either surgery or MWA, but that metastatic recurrence was low with all treatments (and potentially lower with ablative treatments, although this is likely a bias related to tumor grade). Long term survival studies will be useful to better define the role of each treatment modality. Poster 15: Radiofrequency Ablation (RFA) vs. Cryoablation (Cryo) vs. Microwave Ablation (MCW) of T1 Renal Cell Carcinomas (RCC): Outcome Prediction in an Intermediate-Long Term Cohort J.C. Camacho1, N. Kokabi2, W.C. Small2, D. Kies1, H.S. Kim3. 1 Interventional Radiology and Image Guided Medicine, Emory University School of Medicine, Atlanta, GA; 2Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA; 3 Interventional Radiology, Yale University, New Haven, CT. Objective: To investigate prognostic factors after percutaneous ablation of renal cell carcinoma (RCC) in an intermediate-long term cohort. Methods: IRB approved HIPAA compliant 8-year study of 144 consecutive patients (Mean age 65.5 years; 63.1% males, 36.9% females) with 189 biopsy-proven RCC that underwent percutaneous ablation (24.3% RFA, 35.5% Cryo and 40.2% MCW). Imaging follow-up included CT or MRI in all cases (mean follow-up 60.6 r 28.3 months). R.E.N.A.L. (radius, exophytic/endophytic, nearness to collecting system or sinus, anterior/posterior and location relative to polar lines) scores were analyzed to

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determine association with ablation treatment outcomes and complications. Tumor grade, number of probes used and renal function detriment were also evaluated. The characteristic differences between the groups were compared using Chi-Square. Prognostic analysis was carried out utilizing analysis of variance using the SPSS software v20.0 (IBM, Armonk, NY). Significance was set at <0.05. Results: Mean tumor size was 2.2 cm (range 0.6-5.7 cm; mean size RFA 1.95 cm, Cryo 2.38 cm, MCW 2.26 cm; p=0.068) and 49.7% of the lesions measured <2 cm. Technical success rate following a single session was 93.6% (RFA 97.8%, Cryo 91.0%, MCW 93.4%; p=0.12). Mean nephrometry score was 6.51 r 2.05; and the Cryo group had significantly more complex lesions (RFA 5.5, Cryo 7.0 and MCW 6.6, p=0.01). Overall recurrence rate was 10.0% (RFA 10.8%, Cryo 19.4% and MCW 1.3%; p=0.002). The 12-month recurrence rate was 1.5% (RFA 2.1%, Cryo 2.9% and MCW 0.0%; p <0.001). Complication rate was 12.1% (RFA 2.1%, Cryo 17.9% and MCW 6.5%; p=0.162); 74% were Clavien 1, 4.3% Clavien 2 and 21.7% Clavien 3. When comparing the three modalities, no significant differences were noted in post-procedural renal function throughout the follow-up period (p =0.796). Nephrometry score was t8 in 33.8% of lesions, significantly higher in the Cryo group (RFA 12.5%, Cryo 46,8%, MCW 40.6%; p=0.01). When stratifying by R.E.N.A.L score, a score t8 was associated with increased complications (p <0.001), overall recurrence (p <0.001), 12-month recurrence (p<0.001) and lower technical success (p <0.001) across all modalities. Tumor grade (Fuhrman grade 3 and 4) was associated with 12-month and overall recurrence (p = 0.012). Recurrence and complications were significantly higher in patients that required the use of more than one probe (p <0.001). Through out observation period, no significant changes in creatinine level or CKD stage were noted (p =0.353); and cancer specific survival was 100%. Conclusions: R.E.N.A.L. nephrometry score predicts early and overall recurrences, technical success and complications for RFA, Cryoablation and Microwave ablation in the treatment of RCC. No statistically significant differences were noted in technical success, complication rate or renal function following therapy. Poster 16: Thermal Ablation for Metastatic Renal Cell Carcinoma: Safety and Local Oncologic Efficacy S.L. Averill2, E.J. Abel6, J.L. Hinshaw2, M. Lubner5, T. Ziemlewicz1, F. Lee4, S. Best7, S.A. Wells3. 1Radiology, University of Wisconsin, Madison, WI; 2Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI; 3Radiology, University of WisconsinMadison, Madison, WI; 4University of Wisconsin-Madison, Madison, WI; 5University of Wisconsin-Madison, Madison, WI; 6University of Wisconsin-Madison, Madison, WI; 7University of Wisconsin-Madison, Madison, WI. Objective: Approximately 20% of patients with renal cell carcinoma (RCC) have metastases at presentation and nearly half of patients with locally advanced RCC will progress to metastatic disease. While metastectomy can provide durable local control, it remains controversial because improved survival has not been established in prospective trials. However, survival advantage in oligometastatic disease has been demonstrated in several retrospective studies. Given the favorable safety profile and high rate of local tumor control for localized RCC, thermal ablation may be an alternative to metastectomy in carefully selected patients. Therefore, the purpose of this study is to determine the safety and local oncologic efficacy of thermal ablation in metastatic RCC (mRCC). Methods: Retrospective single center review of 18 patients with biopsy proven mRCC (18M/4F), mean age 68r11 treated with percutaneous radiofrequency ablation (2), cryoablation (6) and microwave (14) between 2/2004 and 1/2016. Patient and procedural data were collected including BMI, comorbidities, metastasis size, histology and location. Mean patient BMI was 30.6r4.2 and mean Charlson comorbidity index was 4.5r 2.8 Mean duration of hospitalization was 1 day (range: 0-2). Technical success, presence of local and distant tumor progression were assessed at immediate and serial follow-up imaging. Results: Technical success was achieved for 20 tumors (100%) including 4 lung, 3 adrenal, 2 liver, and 11 soft tissue metastasis. Median tumor diameter was 2.4 cm (range: 0.8-5.8). There were 17 clear cell, 1 chromophobe, 1 papillary RCC and 1 subtype was not specified. Mean clinical and imaging follow-up was 25 months (range: 0-59) and 26 months (range: 0-54) respectively. Two patients were lost to follow-up and were excluded from survival analysis. Local tumor progression (LTP) occurred in 3 patients (19%) at a mean of 11.5 months (range: 3-19). Distant progression occurred in 8 (50%) at a mean of 10.8 months (range: 2-.29). Median overall survival was 24 months. Three patients died of metastatic disease conferring a progression-free survival, cancer-specific and overall survival of 81% (13/16), 75% (13/16) and 75% (13/16). There were 3 Clavien-Dindo grade I-II complications (14%) and 1 Clavien-Dindo grade III-IV complication (5%). Conclusions: Thermal ablation offers durable local control for mRCC with a low rate of procedural complications. The low procedure-related morbidity and abbreviated period of convalescence of thermal ablation relative to surgery offer unique advantages in the complex management of oncologic patients.

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Poster 17: Thermal Ablation of Small Renal Masses: Should Biopsy Take Place Prior to or During the Ablation Procedure? V. Wong4, E.J. Abel3, F. Lee3, J.L. Hinshaw2, T. Ziemlewicz1, M. Lubner3, S. Best3, S.A. Wells3. 1Radiology, University of Wisconsin, Madison, WI; 2Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI; 3Radiology, University of Wisconsin-Madison, Madison, WI; 4University of Wisconsin-Madison, Madison, WI.

Poster 18: Accuracy of CT-Guided, Robot Assisted Needle Placement for Hepatic Artificial Lesions: Comparison Study with Conventional Procedure in Swine Model S. Oh1, J. Seo1, J. Lee1, N. Kim1, H. Kim2, H. Park3. 1Radiology, Asan Medical Center, Seoul, Korea (the Republic of); 2Corporate Technology Institute, Hyundai Heavy Industries Co., Ltd., Yongin-si, Korea (the Republic of); 3University of Ulsan College of Medicine, Asan Medical center, Seoul, Korea (the Republic of). Objective: Purpose of this study is to evaluate accuracy and feasibility of CT-guided, robot-assisted needle placement of hepatic lesion in comparison with conventional CT-guided procedure in swine model with artificial lesions. Methods: The robot system including 5-axis robot arm, a mobile platform with motor controllers, dedicated workstation for planning of needle path, and the navigation system (Polaris Spectra®; NDI, Canada) was developed. It provides useful functions including such as needle path planning, respiration monitoring, laser guidance, automatic needle positioning and guiding. To evaluate the feasibility of the system in needle placement, three swine were used. For preparation, they were anesthetized and ventilated. Under CT guidance (Sensation 16, Siemens, Germany), multiple metallic markers were inserted to the liver. The respiration of the swine was controlled with ventilator and intravenous injection of muscle relaxant. CT scan was performed to localize the target lesion and the CT data was transferred to the system. The spatial relation between swine and the robot system was registered with navigation system. After planning the needle path on workstation, the spatial information was translated to the robotic system. The robot system automatically angulates the needle to the target and depth of insertion is determined. For same targets, conventional CT guided needle insertion was performed. Total of 58 needle insertion trials to 29 artificial target lesions were performed by two radiologists. Using the CT images after the insertion, distance between the target and actual needle tip and angle between preplanned route and actual needle pathway were measured. Each results for same target was compared with paired t-test.

Results: All experiment was done without complication. The distances between the target and the needle tip for robot assisted and conventional procedure was 4.7r2.9mm and 5.2r2.2mm, respectively (p=0.48, paired t-test). There was no significant difference in angular deviation between two procedures (4.0r3.4°, 2.9r1.2°, p=0.14). There was a tendency of short procedure time with robot assistance (5m01sr1m43s vs. 5m47sr1m49s), although the difference was not significant (p=0.08). Since additional CT scanning was performed to correct needle angle in conventional procedures, the radiation dose with robot assistance was two-thirds of conventional procedure. Conclusions: Developed robot system provides comparable accuracy of CT guided needle placement for hepatic target lesion to conventional procedure, in relative short procedure time and with significant decrease in radiation dose.

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Objective: Percutaneous biopsy of small renal masses (< 4.0 cm) targeted for thermal ablation is rapidly becoming standard practice. However, questions remain as to the appropriate timing of biopsy: 1) either in a separate setting before ablation or 2) at the time of ablation. While the latter strategy allows both procedures to be performed in a single setting potentially reducing the rate of complications, it may increase the rate of ablating benign tumors that would not otherwise have required treatment. The purpose of this study is to: 1) compare the rate of non-diagnostic biopsy when performed either prior to or during ablation and 2) based upon biopsy timing, determine how often ablation was performed for oncocytoma or unconfirmed renal cell carcinoma (RCC). Methods: Retrospective review was performed of 280 consecutive patients who underwent percutaneous thermal ablation for a renal mass between 1/2003 and 1/2015. Patients were stratified into two groups: Those who underwent core biopsy in a separate session before ablation (n=197) and those who underwent biopsy during the ablation procedure (n=83). Patient and renal mass characteristics, image-guidance modality, tumor histology and complications were recorded. The rates of non-diagnostic biopsy were calculated. Categorical data was analyzed with the Fisher’s exact test. A p value of < 0.05 was considered significant. Results: Tumor diameter, location and enhancement, rate of cystic and solid renal masses, and guidance modality between cohorts were similar (p>0.05). The skin-to-tumor distance, a factor associated with non-diagnostic biopsy, was greater in the cohort who were biopsied in a separate session before ablation (10.5 cm versus 8 cm) [p=0.001]. The non-diagnostic rate was greater in the cohort who received biopsy during ablation, 14.5% (12/83) vs. 1.5% (3/197) [p<0.001]. The rate of all complications and major complications were similar (p=1.0 and p=0.68). The rate of ablation for oncocytoma was significantly higher when biopsy was performed in the same session as ablation, 15.7% (13/83) versus 3.1% (6/197) [p<0.0001]. Patients were ultimately more likely to have an unknown diagnosis when biopsy was performed in the same session as ablation 30.1% (25/83) versus in a separate session before ablation 4.5% (9/197) [p<0.0001]. Conclusions: Performing percutaneous renal mass biopsy in a separate session prior to ablation is safe, increases the rate of positive histologic diagnosis of SRM, and reduces the rate of treatment for both benign and undiagnosed renal masses. Biopsy prior to ablation may improve comprehensive risk stratification including informed consent, guide decision making for imaging follow-up and reduce healthcare costs by decreasing the rate of unnecessary ablation.

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CT guided needle placement robot for biopsy

A screen shot of preplanning for biopsy on workstation Poster 19: Robot Assisted Percutaneous Ablation of IRE for Pancreatic Carcinoma: Preliminary Experience Y. Xiao. Radiology, PLA General Hosipital, Beijing, China. Objective: To define the accuracy and the procedural performance of robotic assisted IRE ablation of pancreatic carcinoma Methods: With the assistance of MaxioTM EX, 5 patients were performed IRE ablation under CT guidanceAfter the general anesthesia, an enhanced CT scan of abdomen were performed to demonstrate the tumor region, size and anatomical structures, and the image data was transmitted to the workstation of the Maxio. Both automatic and manual tracing of tumor’s contour was performed, the plan was made, including the numbers and the arrangement of IRE probes with the distance from 15-20mm between each probe. After completed the planning, the robotic arm moved automatically to the positon of the patient’s skin determined in the planning, and the radiologist inserted the probe one by one through the bush at the arm to the predetermined depth. After completion of inserting all IRE probes, a CT scan performed to verify the position of the probes. Results: Robot assisted IRE probe inserting were successfully completed in all 5 patients, among them 3 probes were inserted in 1 patients, 4 in 2 patients, 5 in 1 patient and 6 in 1 patient. For all 5 patients, there was an average 2 needles shift from the planning site (1 to 3), the positioning error within 10mm, and a readjustment was performed. The numbers of CT scan were from 4-8, average 5 scan, the time of inserting probes within 20 min. Conclusions: Robotic-assisted percutaneous IRE ablation of pancreatic carcinoma, with inserting all needles in one time, is convenient and easier operate than the conventional positioning of probes in which every needle was inserted step by step, the procedure also reduce significantly operating time and radiation dose to patient.

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refused conventional radiation treatment or chemotherapy were treated with percutaneous cryoablation. 61 lesions were treated (3 or fewer lesions per patient), which were all characterized by lytic bone lesions on CT images, and each with a diameter of less than 60 mm (36 mmr11). Follow-up contrast CT scan was obtained at 1 month after treatment and PET-CT scan was preformed at 6 months thereafter to evaluate treatment outcome and complications. Patient response was measured with Visual Analog Scale (VAS), and recorded prior to treatment and 3days, weekly for successive 4 weeks and 2 months after the procedure. Results: There was no local recurrence 6 months later, and the average maximal standard uptake value (SUVmax) of 61 lesions was reduced from 9.7 to 4.6 (P <0.05). But new metastatic lesions were found on other parts of body in 10 patients. All lesions those were treated appeared no enhancement on the follow-up contrast CT images. The average diameter was reduced from 38mm to 32mm in 43 lesions; and there were no obvious changes in the rest. The mean score for worst pain in a 24-hour period was 6.8 before cryoablation; the score decreased to 4.2 (P <0.05) 1 week after treatment, and to 2.6 (P <0.05) 2 months after treatment. No serious complications were observed. Conclusions: Percutaneous cryoablation is a safe and effective method to treat local lytic bone metastases. Poster 22: Case Control Study of Radioembolization Delivered Through the Surefire Infusion System versus Standard End-Hole Catheter E.A. Lacayo, G. Esposito, A.Y. Kim. Dept of Radiology, Medstar Georgetown University Hospital, Washington, DC.

Poster 20: Video of a Case for Robot Assisted Percutaneous IRE Ablation of Pancreatic Carcinoma Y. Xiao. Radiology, PLA General Hosipital, Beijing, China. Objective: To difine the effetiveness of robot assted probe inserting for the IRE ablation Methods: With the assistance of MaxioTM EX (Perfint Healthcare Pvt. ltd), 5 patients were performed IRE ablation under CT guidance, male 2, female 3, age from 46-62 yrs, among them, 3 patients had a drainage of biliary duct before ablation due to obstruction. Results: Robot assisted IRE probe inserting were successfully completed in all 5 patients. Poster 21: Percutaneous CT-Guided Cryoablation of Lytic Bone Metastases: Clinical Cases Analysis

Objective: The objective of this study is to assess the difference in tumor uptake of resin Y-90 particles delivered by the Surefire infusion system (SIS) versus standard end-hole microcatheters. Methods: Data were collected retrospectively on patients who underwent SIRT at a single institution by a single interventional radiologist. We compared tumor uptake versus normal liver uptake of radioembolic particles in patients that underwent SIRT using the SIS or standard end-hole microcatheter for the delivery of Y-90. Degree of uptake was quantified using single-photon emission computed tomography (SPECT) performed immediately post-procedure and fused to CT or MRI. Regions of interest (ROIs) were drawn on the main lesion and normal liver using a threshold of > 40% of the voxel with maximum counts. We calculated the ratio between the average uptake (counts/cc) of the tumor and normal liver in both patient groups. We then compared both groups and performed statistical analysis using an unpaired t-test. Results: Six patients with diagnosis of metastatic colon cancer, pancreatic cancer or cholangiocarcinoma underwent 9 radioembolization treatments with the SIS in a lobar fashion. Six patients with matching tumor type and hepatic disease burden undergoing lobar treatments with a standard end-hole catheter (Progreat microcatheter, Terumo) served as the control group. Tumor:Normal uptake of radiation was measured in 6 representative right lobe and 3 left lobe lesions. The mean tumor and normal uptake in the SIS group per cc was 97229 counts (range 4528-248472) and 50795 (range 1265-150460), respectively. This is compared with 184296 (range 26385-457207) and 114735 (range 27333-288614) for the end-hole catheter group. The mean T:N ratio for the SIS group was 1.92 (range 1.03-2.67) versus 1.64 (range 0.80-3.15) for the control group. All 9 lobes treated with SIS had a T:N ratio >1 versus 5 of 9 for the control group. The ratio of patients treated with SIS demonstrated the range of increased tumor uptake versus normal liver uptake was 3 to 167 percent, with a mean of 92 percent increased delivery per cc. In contrast, when compared to the 6 patients that were treated using standard end-hole microcatheters, 4 out of the 9 liver lobes treated in this group, had increased normal liver uptake when compared to tumor uptake. The 5 out of 9 liver lobes that did demonstrate increase tumor uptake, demonstrated a range from 2 to 215 percent with a mean of 64 percent increased delivery per cc (p=0.48). Conclusions: We found a trend towards but not a statistically significant increase in T:N uptake of resin Y-90 particles when delivered with SIS. Our study is limited due to small sampling and its retrospective nature. Further studies are needed to assess the true impact of SIS in augmenting tumoral delivery of Y-90 particles. Poster 23: The Role of Percutaneous CT Guided Biopsies of Retroperitoneal Lesions: Are They Really Safe and Effective?

X. Zhang2, Y. Xiao1. 1Radiology, PLA General Hosipital, Beijing, China; 2 Radiology department, The General Hospital of People’s Liberation Army, Beijing, China.

L.T. Dias1, C.T. Amancio2, P.C. Viana1, C.C. Leite2, G.G. Cerri2, M.R. Menezes2. 1Radiology and Image Guided Intervention Service, Cancer Institute of São Paulo (ICESP), São Paulo, Brazil; 2Radiology and Imaged Guided Intervention Service, Sírio Libânes Hospital, São Paulo, Brazil.

Objective: To prospectively evaluate the safety and efficacy of percutaneous cryoablation in patients with painful lytic bone metastases. Methods: Written informed consent was obtained in this prospective study that was approved by the local ethics committee. From 2009 to 2014, 36 patients (21 men,15 women; age range,29-82 years; mean age,53 years) were enrolled with bone metastases originated from lung cancer, breast carcinoma, etc. CT and PET-CT sans were preformed before treatment. These patients who did not respond to or

Objective: The purpose of this study was to demonstrate the efficacy and accuracy of CT-guided needle biopsy for retroperitoneal lesions. Methods: This study included 218 patients with retroperitoneal lesions that were referred for percutaneous imaging-guided biopsy consecutively from 2007 to 2014. The patients were 132 men and 86 women (age ranged between 18 - 95 years). The maximum diameter of the target lesion ranged from 0,8 to 25 cm in size. In

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191 patients were used coaxial needle under a CT or CT-fluoroscopy guidance and with the patient under local anesthesia. Results: No major complications were seen and were noted local hematomas in three patients (1,4%), without need medical interventions. The procedure was effective with histopathological conclusive results in 93,1% of cases. Of these, 54,2 % represented metastasis. Conclusions: Image guided biopsy is an activity widely accepted in current medical practice, due to its excellent results and low complication rate. The retroperitoneal biopsy guided by CT was shown to be safe and effective. Poster 24: A Ferritin-Based Nanoconjugate MRI Contrast Agent Targeting Necl-5 as a Tumor Specific Marker

Objective: A ferritin-based nanoconjugate was previously demonstrated as capable of binding to Necl-5 cell surface glycoprotein in an in vitro model. This study examined the ability of the conjugate to bind to tumor cells in a xenograft mouse tumor model against a nontargeted ferritin with the same iron loading. Methods: Rat prostate epithelial cells were cultured and injected (107 cells) into the left rear flank of female beige/nude/xid triple deficient mice. 10-12 days were allowed for tumor growth. Ferritin conjugate was administered either via tail vein injection (12 animals), or direct injection (14 animals) into tumors (two groups, with corresponding controls). Time series multi-spin echo MR imaging was carried out to assess R2 vs time (R2=1/T2). Data were analyzed assuming a Gaussian distribution using PROC GLIMMIX in SAS 9.4® Software for Windows (SAS Institute, Inc., Cary, NC). Significance level was established a priori at pd0.05. R2, was modeled with time, by condition (conjugate vs. control), where observations were nested within mouse. As a conservative effort, multiple comparisons were calculated using Bonferroni correction. Data were analyzed for both direct and tail vein experiments. Results: Figure 1. R2 MR images of mice with tumor (red arrows) derived from rat PEC SAI cells suggest utility of tail vein administered anti-Necl-5/ferritin nanoconjugate as a novel contrast agent. Note increase in R2 across the tumor, which is not seen in the control. Figure 2. A plot of R2 response of the conjugate versus control (ferritin only) over time (80 minutes). The samples were administered via tail vein injections (0.8 mg, 300 PL). Figure 3. A plot of R2 response of the conjugate versus control (ferritin only) over time (144 minutes). The samples were directly injected. Figure 4. R2 map example for the direct injection case for control and targeted ferritin 24 and 90 minutes post injection. Targeted conjugate is retained in the tumor as evidenced by increased R2 (reduced T2). Figure 5. Immunofluorescence (Alexa Fluor® 488 Antibody) responses of tumor (Panel A and B) and liver (Panel C and D) tissues acquired from the mice with the tail vein injection of sample (0.8 mg, 300 PL). The sample is either ferritin only (control Panels A and C) or the conjugate (Panels B and D). Scale bar is 50mm. Conclusions: The nanoconjugate interacts strongly and selectively with Necl-5 overexpressing tumor cells. Varying degrees of R2 increase within the tumor mass likely reflects tumor heterogeneity and distribution patterns of the conjugate.

WCIO Abstracts

E. Walsh2, K.C. Park1, D. Mills3, S. Lim4, B. Sana4, V. Frank3, B. Kenyon3, G. Baird3, K. Brilliant3, D.E. Dupuy1. 1Diagnostic Imaging, Rhode Island Hospital / Brown Medical School, Providence, RI; 2Brown University, Providence, RI; 3Rhode Island Hospital, Providence, RI; 4NanYang Technical University, Singapore, Singapore.

Poster 25: Targeting “Tough” Lesions during Renal Ablations: A Pictorial Essay A. Sawas2, K. Stewart1, D. Butani2. 1University of Rochester, Pittsford, NY; 2Imaging science, University of Rochester, Rochester, NY. Objective: To provide an overview of ablation of renal cell carcinoma including indications, patient selection, benefits, and risks. To present procedure techniques to perform ablation including lesions that are technically challenging. To present the imaging appearances of complications after ablation. Methods: Present selection criteria and patient evaluation for percutaneous treatment of renal cell carcinoma. Discuss types of percutaneous ablation including radiofrequency ablation, microwave ablation and cryoablation. Discuss and illustrate with images the advanced targeting techniques during percutaneous ablation using the following adjuncts: hydrodissection, pneumo-dissection, balloon separation and protection of vital structures, lateral approaches in supine position, trans-diaphragmatic approach, transhepatic approach, adjuvant pre-RFA embolization to reduce heat-sink, and ethanol injection to treat periphery of tumor near vital structures as an aid to cryoablation. Name and illustrate complications of these techniques on post procedure imaging and evaluation including hemorrhage, nontarget ablation, ureteral stricture, urinoma, colonic perforation, fistula, pneumothorax, track seeding, and tumor recurrence. Results: Renal cell carcinoma (RCC) is one of the 10 common cancers in the United States. Percutaneous ablation is useful for management of renal masses in patients who are not candidates for surgery, post-partial nephrectomy, with a unilateral or transplanted kidney, prefer minimally invasive techniques, or at risk for multiple RCCs over their lifetime. Several techniques are available for successfully targeting and safely treating technically challenging lesions during percutaneous ablation. Long-term clinical and oncologic outcomes following percutaneous ablation are comparable to partial nephrectomy, however, ablation therapy offers a greater advantage at preserving renal function Conclusions: Renal ablative therapy has proven to be of immense benefit in the treatment of renal masses. This is especially true in the renal-impaired patient, or the non-surgical candidate. The location of the lesion can make targeting challenging. Careful consideration must be given to adjacent vital structures and the size of the treatment zone.

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Poster 26: Safety and Efficacy of Treatment with CT-Guided Percutaneous IRE: A New Minimally Invasive Ablative Therapy

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Y. Wei1, Y. Xiao2. 1Radiology, Chinese PLA General Hospital, Beijing, China; 2Radiology, PLA General Hosipital, Beijing, China. Objective: Irreversible electroporation(IRE) is an emerging ablative therapy has now been widely recognized. It is a kind of local treatments induced the cells death by apoptosis through irreversibly disrupting cellular membrane integrity. Compared with IRE ablation during open surgery,CT-guided percutaneous IRE ablation is a minimally invasive treatment of locally advanced malignant tumors that have been increasingly utilized. We aimed to assess the safety and efficacy of CT-guided percutaneous irreversible electroporation(IRE) in the treatment of patients with locally advanced tumors in different anatomical position. Methods: From July 2015 to December 2015,patients in our hospital with unresectable local advanced malignant tumors were treated with IRE under the guidance of CT,and recorded in the clinicaltrials.gov database(NCT02567734). We monitored the blood tests and image changes regularly at postoperative day 3, 1 and 3months. The overall survival and complication rate were evaluated. Results: IRE was performed in a total of 28 patients (including 21 pancreatic cancers,3 hilar cholangiocarcinomas,3 retroperitoneal tumors,1 abdominal metastatic tumor) with different unresectable malignant tumors. All the procedures were performed successfully. With a median follow-up of 5 months, there were no mortalities occurred,6 patients suffered complains,3 developed abdominal pain and other developed vomit. Compared with the preoperative images,CT/MR imaging after IRE ablation demonstrated areas of nonenhancement in the treatment zone and there was a decrease of 17.1% in the size of the target tissue in the postoperative 3months. There was no disease progression and recurrence occurred. Conclusions: CT-guided percutaneous IRE is a safe and effective procedure in patients with local advanced malignant tumors and may represent a new minimally invasive option in the treatment and multimodality management of these diseases in the future. Poster 27: Outcomes after Portal Vein Stenting in Cancer Patients G.C. Fine, F.E. Boas, J.C. Durack, A. Covey, G.I. Getrajdman, J.P. Erinjeri, L.A. Brody, M. Maybody, N. Muallem, K.T. Brown. Radiology, Memorial Sloan Kettering Cancer Center, New York, NY. Objective: To evaluate the safety and efficacy of stenting malignant portal vein occlusion or stenosis to treat bleeding varices, ascites, liver failure, or thrombocytopenia. Methods: Between 2008 and 2015, 20 patients with malignant compromise of the portal vein were referred for percutaneous portal vein stent placement to treat bleeding varices (n=9), ascites (n=7), varices and ascites (n=1), liver failure (n=2), and thrombocytopenia (n=1). Imaging, clinical notes, additional procedures, and laboratory values were evaluated to determine technical and clinical success rates as well as complications. Overall survival and stent patency were evaluated using Kaplan Meier analysis. Results: Portal vein stent placement was technically successful in 19 of 20 (95%) patients. 18 of 19 patients were stented from a transhepatic approach. In one patient, a trans-splenic approach was necessary to cross the occlusion. In the one technical failure, referred for variceal bleeding, the occlusion could not be crossed and the patient underwent splenic artery embolization. Two patients had “kissing stents” placed (portal vein into the SMV and IMV; portal vein into the left gastric vein and SMV). Immediately after stent placement, portography showed improved hepatopedal flow in 18 of 19 patients, and decreased or no filling of varices in all 9 patients with that indication (Figure 1). The major complication rate was 5%: one immediate in-stent thrombosis requiring thrombolysis. Mean overall survival after stenting was 6.6 months (Kaplan Meier estimate). Primary stent patency at 6 months was 58% (Kaplan Meier estimate). 5 of 9 (56%) patients who underwent stenting for variceal bleeding had no further bleeding episodes (mean follow up interval of 5.5 months). Of the 8 patients who underwent stent placement for ascites, 1 had decreased ascites, 5 had evidence of persistent or increased ascites, and 2 had no follow up. Of the 2 patients with liver failure, 1 patient with a concurrent biliary drain had improved liver function after portal vein stenting and 1 had persistent liver failure and received a liver transplant. In the patient who had the stent placed for thrombocytopenia, the platelet count returned to normal within 2 weeks after stent placement. Conclusions: Transhepatic stenting of the portal vein is safe and potentially effective for treating variceal bleeding secondary to malignant portal vein compromise. Stenting may benefit patients with thrombocytopenia, but does not seem to be an effective treatment for ascites.

Poster 28: US/CT Fusion-Guided Needle Placement with Mini Cameras Mounted on Ultrasound: A Phantom Study J. Thai1, R. Seifabadi1, S. Xu1, E. Basafa2, M. Hossbach3, P.J. Stolka2, B.J. Wood1. 1Department of Radiology and Imaging Sciences, The National Institutes of Health, Bethesda, MD; 2Clear Guide Medical, Baltimore, MD; 3Clear Guide Medical, Baltimore, MD. Objective: Inaccurate needle tip placement in interventional procedures results in failed procedures and complications. Devices with platforms that provide tracking and guidance can improve accuracy. The Clear Guide Scenergy system uses a set of stereo view cameras mounted on the ultrasound (US) probe to provide live tracking of needle and fiducial markers on a patient, allowing computed tomography (CT) images to be fused with real time US. In clinical scenarios where the target lesion is not clearly visible on ultrasound, an US-CT fusion technique can be used to define target location and facilitate accurate targeting. We performed a phantom accuracy study to compare the two approaches - US vs US-CT fusion. Methods: A Mindray M7 US scanner, the Clear Guide Scenergy system and a CIRS multimodality US abdominal phantom were used, with automatic landmark-based registration. For fusion targeting, we created 10 mm virtual target points not visible on US in the liver and kidney, in CT coordinates. Three ultrasound operators with different levels of expertise (novice, intermediate and expert) were familiarized with the Clear Guide Scenergy system prior to experiments. Each individually inserted a needle towards the targets, first with US only, where the target was not visible on US and the operator was guided solely by static, pre-interventional CT images displaying the intended target. This was followed by another insertion using the US-CT fusion guidance, where the location of the target was marked and identified on the ultrasound screen. Comparison was made with regard to needle placement accuracy (distance from needle tip to center of target). Results: The accuracy between US vs US-CT fusion was significantly different (p=0.03) among novice and intermediate operators but not with the expert operator. When analyzed individually, novice and intermediate operators had better accuracy with fusion (19.7mm vs 5.1mm) while the expert operator’s accuracy was quite similar, but slightly better with ultrasound (4mm vs 5.67mm). Conclusions: Ultrasound with mounted mini-cameras enables US-CT fusion navigation, which is beneficial for novice and intermediate operators. This technique significantly improves the accuracy for targeting lesions that are not clearly visible on US. Poster 29: Clinical Application of CT-Guided Percutaneous Cryoablation on Desmoid Tumor Y. Wei1, Y. Xiao2. 1Radiology, Chinese PLA General Hospital, Beijing, China; 2Radiology, PLA General Hosipital, Beijing, China. Objective: To investigate the clinical value of palliative treatment of desmoid tumor by cryoablation. Methods: Five cases with recurrent desmoid tumor were analyzed retrospectively, and CT-guided percutaneous cryoablation was done. The tumor size, density, changes in the way to strengthen, the clinical symptoms and hematological indexs before and after surgery were compared, and the occurrence of postoperative complications was analyzed. Results: Five patients were successfully treated. Two patients were treated in 3 times and 4 times respectively, postoperative enhancement CT scan showed obvious liquefaction necrosis in ablation zone with clear boundaries, varying degrees strengthening was found in the residual tumor. The tumor response rate was 80% (4/5) after 12 months. Varying degrees of improvement was found in clinical symptoms. The main postoperative complications were pain, fever, soft tissue swelling, urination, perineal numbness; one patient appeared skin frostbite; hematological index of patients elevated in acute phase.

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Conclusions: The characteristics of CT-guided percutaneous cryoablation are less traumaric, and can effectively reduce the tumor burden, relieve symptoms, it can be used as an effective method to treat recurrence desmoid tumor palliatively. Poster 30: Image-Guided irreversible Electroporation (IRE) of Hilar Cholangiocarcinoma and Pancreatic Carcinoma Using Novel Robotic Guidance Y. Wei1, Y. Xiao2. 1Radiology, Chinese PLA General Hospital, Beijing, China; 2Radiology, PLA General Hosipital, Beijing, China.

Methods: Pre-operative assessment of the lesion is done with CT scan or MRI. Pre-procedure work up includes CBC, coagulation profile, RFT, ete. Most of these procedures are performed under local anesthesia and as day care and no fasting required. For procedures requiring general anesthesia (e.g. radiofrequency/ microwave ablation), overnight fasting is required and patient requires admission. These procedures are done under CT guidance (Siemens sensation 16 slice, Germany) or fluro guidance (Artis Zee, Siemens, Germany/GE Innova 4100, General Electric Healthcare, USA). Depending on type of procedure, biopsy needles/RFA electrode is advanced into the fat planes in close proximity to the lesion and minimum volume of 0.9% saline solution/ dextrose/dilute contrast medium/hydro dissection gel materials/ air etc is injected to displace the adjacent vital viscera or vasculature to allow proper passage of the needle through the space created by hydro and air dissection, which varied from 20 to 50 ml. Results: Inaccesible region of interest have been successfully targetted using hydrodissection. In some cases even air was used eg. creating controlled pneumothorax for mediastinal node biopsy. 0.9% normal saline was generally used for hydrodissection and creating a path for needle to approach the target. However, 5% dextrose was injected in cases of radio frequency ablations as normal saline tends to conduct heat and cause complications. Conclusions: Hydro and air dissection offers safe, precise and effective aid to different techniques in field of intervention radiology and has resulted in significant reduction in morbidity.

Poster 31: Image-Guided Adhesiolysis for Percutaneous Thermal Ablation A. Worakitsitisatorn1, D. Lu2. 1Radiological Sciences, University of California Los Angeles, Los Angeles, CA; 2Radiological Sciences, University of California Los Angeles, Los Angeles, CA. Objective: To describe the technique of image-guided adhesiolysis for percutaneous ablation of subcapsular liver tumors and to present our initial experience. The reader will be able to understand indication, our procedural technique and potential complications. Methods: Principle: Hydrodissection has been well described as an adjunctive technique to provide additional safety to adjacent organs when renal and retroperitoneal tumors are treated by percutaneous thermal ablation. Similary, creation of artificial ascites is now widely practiced to protect diaphragm and adjacent bowel when subcapsular liver tumors undergo thermal ablation. The latter technique, however, would not be effective in patients whom liver is adhered to the diaphragm and adjacent organs. Therefore, a technique to percutaneously lyse the adhesions may be useful in this patient population. Results: Technique: We present our initial experience using image-guided adhesiolysis to treat subcapsular liver lesions in patients who had prior abdominal surgery. In essence a needle is directly targeted under ultrasound to the interface requiring separation, and progressive hydrodissection with dynamic repositioning of the needle tip under real-time ultrasonography is performed. This way, even larger surface areas along the diaphragm can be protected from thermal damage. Conclusions: After reviewing this topic, the readers will understand the principle and technique of percutaneous image-guided adhesiolysis, and how this technique may be used to effectively provide thermal protection of adjacent organs in patients undergoing percutaneous ablation of subcapsular liver tumors post abdominal surgery.

Pre RFA PET-CT shows lesion near gall bladder fossa. Hydrodissection with 5% Dextrose done to create barrier. Rfa probe intoroduced with complete ablation of lesion.

Poster 32: Application of Air and Hydrodissection in Interventional Radiology: A Pictorial Review R.S. Chivate2, A. Singh1, S. Kulkarni3, N. Shetty4, A. Polnaya5, K. Gala1, V. Bakare6. 1Radiology, Tata Memorial Centre, Mumbai, India; 2 Interventional Radiology, Tata Memorial Hospital, Thane, India; 3 Tata Memorial Hospital, Mumbai, India; 4Interventional Radiology, Tata Memorial Hospital, Mumbai, India; 5Interventional Radiology, Tata Memorial Hospital, Mumbai, India; 6Interventional Radiology, Tata Memorial Hospital, Mumbai, India. Objective: To review different approaches and techniques employing hydro dissection. The spectrum of interventional radiology has been on the rise and now successfully covers percutaneous pigtail catheterisation, image guided biopsy, ablation of anatomically difficult accessible masses. Approach to these masses is often assisted by hydro or air dissection to negotiate and safeguard vital structures in close proximity. Techniques using hydro and air dissection include biopsy of retroperitoneal structures, i.e. adrenals, pancreas, nodal masses; radiofrequency or microwave ablation of liver/renal mass etc.

Epidural dissection using 5% dextrose and air for radio frequency ablation of L3 pedicle osteiod osteoma.

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Objective: To investigate the safety and accuracy about robotic assisted CT-guided percutaneous IRE of hilar cholangiocarcinoma and pancreatic carcinoma. Methods: CT-guided percutaneous IRE ablation were performed on 12 patients (8 pancreatic tumors and 4 hilar cholangiocarcinomas) with the assistance of a robotic positioning system. Postoperative CT scans were conducted for evaluating needle placement and procedure-related complications. The complication rate,accuracy of probe placement, number of readjustments were recorded and compared with the prospective IRE received patients (without using robotic system). Results: Improved needle accuracy and optimised probe geometry are observed during CT-guided percutaneous IRE with use of a robotic assistance device. No needl positioning-related complications were found. No mortalities occurred. IRE precedures were successfully completed in these 12 patients. 3-6 needles were used in every procedure. In total 11 times(average 0.9) of needle readjustment were noted,61% percent lower than the freehand needle insertions. No blood vessels and nerves injury. Conclusions: This study demonstrated that robotic-assisted planning and needle placement appears to be safe with high accuracy during performing CT-guided percutaneous IRE of hilar cholangiocarcinoma and pancreatic tumor.

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Poster 33: MR-Guided Interventions in the Upper Abdomen: Reviewing Technical Parameters to Optimize Success

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A. Chon1, S. Tatli2. 1Abdominal Imaging and Intervention, Brigham and Women’s Hospital, Boston, MA; 2Abdominal Imaging and Intervention, Brigham and Women’s Hospital, Boston, MA. Objective: MR guided biopsy and ablations in the upper abdomen are difficult to perform due to constraints on access in a closed-bore system, respiratory motion, and magnetic susceptibility artifacts. Outcomes of such procedures have already been validated in prior studies. The goal of this educational exhibit is to highlight the technical considerations when designing an optimized protocol that can be used for targeting and monitoring during such interventions. Methods: We retrospectively reviewed our MRI-guided procedures, including at least 2 biopsies and 48 ablations in the upper abdomen in last 5 years and noted technical parameters used to facilitate such procedures. Upper abdomen was defined as any intra-abdominal lesion above the level of the kidneys. Results: Breath-hold acquisitions are essential to obtain images without respiratory artifact; use of fast spin echo T2 or gradient echo (GRE) sequences with limited sections just enough to cover anatomy of interest allow for optimal visualization of the tract and target. These sequences also need to be optimized to allow for maximal reduction of blooming artifact. Further confirmation can be made by obtained in multiple planes, which can increase confidence in position of the needle despite the obscuration of the exact location by blooming artifact. Other important technical maneuvers that help facilitate the procedure include optimal positioning of patients to reduce motion and displace adjacent critical organs, as well as careful selection of anesthesia used. When monitoring the ablation zone, short interval scans can provide near real-time evaluation with high soft tissue resolution and no concern for radiation. Dynamic adjustments can be made to the power of the thermal agent to avoid critical structures like the diaphragm, gallbladder, stomach, bowel, and heart. Conclusions: An optimized imaging protocol coupled with detailed pre-procedure planning enables MR guided interventions to serve as a useful problem solving tool for lesions in the upper abdomen that are otherwise difficult to target under other modalities.

Ultrasound image of wire loc placement, corresponding to gross specimen

Poster 34: US Guided Wire Localization for Non-Breast Lesions with Difficult Direct Visualization S.B. Keller, K. Dittmar. Radiology, The Ohio State Wexner Medical Center, Columbus, OH. Objective: Image guided wire localization is a well described clinical standard for aid in surgical excision of breast malignancies. This use has been expanded to include lymph node excision and directed excision of recurrent parathyroid tumors. We have utilized image guided localizations of tumors in a variety or peripheral tumors immediately prior to surgical resection. This benefits the patient and surgeon by decreasing operating room times and complete surgical excision. Methods: A review of the Body Interventional Radiology database was used to identify patients who underwent image guided localization under US and CT prior to surgical excision of various lesions. The electronic medical records were accessed to obtain imaging records, surgical operative reports and pathology reports for three patients who were identified from 6/19/14 - 12/23/15. These records were used to document patient sex and age, location of mass, indication for procedure, biopsy and wire placement technique, surgical technique and complications, and biopsy size and results. The operative times, R0 resection by pathology and imaging were reviewed. Results: Wire localization and fiducial placement were utilized for lung lesions, nerve sheath tumors, demoed tumors and sarcomas. All patients except one had a successful image guided tumor localization. All lesions demonstrated accurate placement of the localization device. The one failure was for a lung lesion where the fiducial was placed into the pleura. Operative times were less than one hour. No complications were reported. Conclusions: Image guided tumor localization is a widely accepted and commonly used technique aiding in conservative surgical excision of breast malignancies. In our case series this technique was expanded to include peripheral lesions and aid in the resection of those tumors that are potentially difficult to detect under direct visualization. This can potentially save on time under anesthesia for the patient and increased likelihood of total enbloc resection of the lesion.

Poster 35: Trends for Using Lipiodol-Doxorubicin versus Drug Eluting Beads-Doxorubicin for Transarterial Chemoembolization in Unresectable Hepatocellular Carcinoma: A Single Center Experience A.S. Moustafa1, A.K. Abdel aal1, D. Redden2, S. Saddekni1, D. DuBay3. 1 Department of Radiology, University of Alabama at Birmingham, Birmingham, AL; 2Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL; 3Department of Surgery, University of Alabama at Birmingham, Birmingham, AL. Objective: Transarterial chemoembolization (TACE) is a non-curative treatment for unresectable hepatocellular carcinoma (HCC). Several combinations of chemotherapeutic agents and embolic material have been used for the treatment of HCC. However, there is not enough data available in the literature to compare the outcomes of these materials or mixtures. The present study was performed to evaluate the trends for using lipiodol-Doxorubicin based conventional TACE (cTACE) compared to drug eluting beads-Doxorubicin TACE (DEBS-TACE) in HCC patients and compare the survival outcomes and tumor response between the two groups. Methods: We retrospectively reviewed the medical records of 412 patients who had their first TACE between January 2008 and December 2014. A total of 314 patients were included in the study. We compared the survival outcomes of cTACE (n=139) versus DEBS-TACE (n=175). The primary endpoint was overall survival, and secondary endpoint was tumor response rate which was categorized according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Results: There was no significant difference between the two groups in the baseline characteristics. However, DEBS-TACE was significantly utilized more often with multifocal disease (1.8r1.3 vs. 1.5r1.7; p=0.01) and there was a trend towards greater utilization of DEBS-TACE with increasing total axial tumor diameter (6.5cmr5.0 vs. 5.7cmr3.6; p=0.09) compared to cTACE. On univariate analysis, Child-Pugh class B and C (p<0.01, p=0.04) and total tumor diameter (p=0.01) were associated with worse survival. After controlling for significant covariates, the DEBS-TACE group showed a longer median survival of 22.3 months compared to 19.7 months in the cTACE group (p=0.04). Conclusions: The current study demonstrates a trend towards using DEBS-TACE in HCC patients with multifocal disease and large total axial tumor diameter. Although

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no significant difference in tumor response was noted, survival was significantly superior in the DEBS-TACE group compared to cTACE group.

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treatment, didn’t received TACE anymore. With the tumor progressed, the patients died of multiple organs failure 3 months after TACE. Conclusions: Ruptured HCC, liver abscess, pulmonary lipiodol embolism and biloma are all rare and fatal complications. They should be considered if patient develops symptoms which are hard to explain by postembolization syndrome. It’s never too late to identify and treat them in early time.

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Crude, unadjusted post-TACE survival in conventional transarterial chemoembolization group and drug eluting beads transarterial chemoembolization group.

Figuer1. CT showed a gigantic liver tumor(A),TACE procedure was finished(B). 3 days later CT showed a gas-containing liver abcess; gas-fluid level around liver capsule (white arrow) and gas around spleen(black arrow), lipiodol shadows in both lungs(white arrow). (C, D). Percutaneous transhepatic drainage were carried out immediately(E,F)

Adjusted post-TACE survival in conventional transarterial chemoembolization group and drug eluting beads transarterial chemoembolization group. Poster 38: Case Report:HCC was Complicated with Tumor Rupture, Liver Abscess, Pulmonary Lipiodol Embolism and Biloma Post-TACE Z. Wu. The Affiliated First Hospital Of Zheng-zhou University, Zhengzhou 450000, Henan, China, Zhengzhou, China. Objective: TACE is recommended as the first-choice for unresectable HCC, the overall complication rate of TACE is relatively low to 2.9%, no mention to severe side effects such as liver abscess; lipodol ectopic embolism, intrahepatic biloma formation, tumor rupture, may develop leading to death. To our best knowledge, there was no report concerned four complications, we performed a retrospectively analysis one case. Methods: A 65-year-old male with a history of hepatitis B virus for 20 years presented with right upper quadrant pain. Biochemiacal examination showed AFP>1200ng/ml. On the abdominal CT, a 18x17cm hepatic mass was identified. The patient was referred to a transcatheter arterial chemoembolization (TACE). Hepatic artery angiogram showed tumor staining without arterovenous shunt. The feeding arteies were superselective catheterized with SP microcatheter(Terumo, Japan), the mixture of 20mg pirarubicin and 30ml lipiodol were infused, then the arterial lumens were closed off with 350-560Pm PVA particles. The second day postoperation, patient complained of chest distress, dyspnea, tachypnea with 40°C hyperthermy. ECG monitor indicated oxygen saturation(SPO2) fluctuated around 90%. Physical examination showed depression of respiratory sounds in inferior lobe lung, Blood gas analysis and abdominal CT were carried out immediately, the arterial partial pressure of oxygen(PaO2) dropped to 60 mmhg, which demonstrated a serious hypoxemia; CT revealed a mass filled with gas-lipiodol density, free intraperitoneal air around liver and spleen, lipiodol shadows deposited in both lungs. The diagnosis was HCC ruptured into abdominal cavity, liver abscess and pulmonary lipiodol embolism(PIE) Results: Respiratory symptoms recovered 5 days later by timely therapy. External drainage was carred out when abscess confirmed,yellow pus effused around drainage tube continuously, biloma was considered. Then the paitient received supportive

Figure 3. 3 month later, CT showed metastasis focus in liver capsule(white arrowhead) and HCC progressed, a tumor thrombus was detected in inferior vena cava (white arrow). Poster 39: Percutaneous Electrochemotherapy of Malignant Main Portal Veins Thrombosis: A Prospective Case Series L. Tarantino2, G. Busto3, A. Nasto3, R. Fristachi3, L. Cacace3, M. Talamo3, P. Ambrosino4, P. Gallo1, P. Tarantino4, C. Accardo3. 1Campus Biomedico University, Rome, Italy; 2Department of Surgery, Interventional Hepatology Unit, Pagani, Italy; 3“A.Tortora” Oncology Hospital, Pagani, Pagani, Italy; 4Federico II University, Naples, Italy. Objective: Cirrhotic patients with malignant main portal vein thrombosis (MMPVT) from Hepatocellular Carcinoma (HCC) are excluded from any known curative treatment. Electrochemotherapy (ECT) is a non-thermal local tumor ablation modality using electroporation which enables chemotherapeutic agents to enter tumor cells without affecting stromal structures and normal cells proximal to the tumor. We treated with ECT, in a prospective study, a series of patients with liver cirrhosis and MMPVT from HCC. Methods: Six patients underwent pre-treatment three-phase abdominal computed tomography (CT), contrast enhanced ultrasound (CEUS), and ultrasound (US) guided percutaneous biopsy of the thrombus and the treated tumor. Four to six electrode-needles were inserted percutaneously around the thrombosed portal vessel. Eight minutes after intravenous injection of a Bleomicin bolus (15,000 IU/m2), electric pulses were delivered (Cliniporator Vitae - IGEA, Carpi, Italy). Short term control of efficacy of the ECT was performed with CEUS intraoperatively and after 24 hours. All patients started enoxaparine and they were followed up with monthly

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color-doppler US (CDUS) and CEUS for six months. CT was performed after 3 months after treatment or before in cases showing recanalization of treated portal vein at monthly CDUS. Results: The follow-up ranged from 3 to 12 months. All patients left the hospital one day after treatment. No major complication was reported. Post-treatment CEUS demonstrated complete absence of enhancement of the thrombosis in all cases. Post treatment biopsy showed severe involutive changes of tumor cells with cellular apoptosis and areas of necrosis. In 2 cases, the specimen showed normal endothelium and normal stromal aspects of portal vein wall. The first patient (12 months follow-up) showed a completely patent portal vein within 2 months from the ECT. 2 patients (8 and 6 months follow-up) showed partial recanalization of the treated portal vessel. The other 3 patients (3, 3, and 5 months follow-up, respectively) showed still avascular thrombus. Conclusions: ECT seems an effective and safe procedure for curative treatment of MMPVT. This technique does not affect hilar biliary structures and vessels. Long term results on larger series of patients are needed to confirm these preliminary results.

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in the non-CMM group with no significant difference in the number of tumors in each patient between groups (Mann-Whitney U test, p value=0.43). Two patients in non-CMM HCC group (3 total tumors) were transplanted after TACE prior to follow up imaging. The first post-TACE responses in CMM HCC tumors were not significantly different from non-CMM patients as detailed in Table 1 (p=0.1). Despite higher local recurrence following TACE and OLT in CMM group, none of these reached statistical significance. At the end of 2 years and following initial TACE and OLT, CMM HCC patients had significantly lower survival compared to the non-CMM patients (56.7% versus 84.8% alive, respectively, p=0.006). Conclusions: The initial response to TACE of CMM HCC is similar to conventional HCC, and thus remains an appropriate bridging therapy to OLT. However, the postTACE and OLT 2-year survival is significantly lower in patients with CMM HCC compared to conventional HCC. Table 1:

Poster 40: Portal Vein Stenting to Reverse Liver Failure and Enable Embolotherapy N.D. Moradzadeh, D.Y. Sze, J. Louie. Radiology, Stanford University Medical Center, Redwood City, CA. Objective: To evaluate the reversibility of hepatic failure by portal vein stenting in patients with obstructive portal vein tumor thrombus (PVTT) not eligible for liver-directed therapy (LDT). Methods: Portal vein stenting performed for hepatic insufficiency suspected to be due to PVTT between 11/2009 and 9/2015 was reviewed. Patients with elevated total bilirubin (TB) and central PVTT were considered prohibitive for embolotherapy, and were treated by portal stenting. 7 patients (6 hepatocellular carcinoma and 1 post-transplant lymphoproliferative disorder) underwent portal vein stenting; 3 of the left portal vein, 2 of the right portal vein, and 2 of the main portal vein. One patient was Child A, 4 were Child B, and 2 were Child C with TB ranging from 1.6-7.3. Absolute volume and proportion of tumor-free liver that was revascularized was calculated using 3-D volumetric reconstruction. Pressure gradients were measured before and after stenting. Hepatic function was followed, and patients were reevaluated for embolotherapy. Results: Portal vein stenting (5 covered stent-grafts and 2 sets of bare stents in bifurcated “Y” configuration) were performed. Five (71%) patients had improvement of liver function with normalization of TB, allowing 4 (57%) to proceed with LDT. All of the right and main portal vein stent patients (revascularized volumes from 970 - 3175 ml and proportions from 57–100%) and one of the left portal vein stent patients (571 ml and 24% volume revascularized) showed improvement in liver function to allow LDT. In the other 2 patients with worsened liver function, both underwent left portal vein stenting (revascularized volumes from 727-730 ml and proportions from 34-43%) and 1 underwent concurrent chemoembolization at the time of stenting. All patients had a significant decrease in the pressure gradient (8.4 vs 0.6, p=0.003). There were no procedural complications. Conclusions: Poor liver function precluding liver directed therapy in patients with portal venous obstruction from portal vein tumor thrombus may be mitigated by portal vein stenting, facilitating subsequent chemoembolization or radioembolization. Volume (or proportion) of revascularized liver may be predictive of benefit.

Poster 42: Presence of Hepatic Shunts in Patients with Non-Operable Hepatocellular Carcinoma is a Predictor of Increased Mortality

Poster 41: Outcomes of Neoadjuvant Transarterial Chemoembolization (TACE) in Cirrhotomimetic Hepatocellular Carcinoma in Comparison to Non-Cirrhotomimetic Hepatocellular Carcinoma

Poster 43: US HCC Screening Behavior Before and After Implementation of a Structured Reporting Initiative

C.W. Bailey, J.M. Kingsbury, B.T. Steadman. Radiology, West Virginia University, Morgantown, WV. Objective: Locoregional embolization therapy, either with chemoembolic or radioembolic agents, is an effective treatment of HCC in nonsurgical patients with candidates having an overall survival of 16 months1. Portal vein invasion which is seen in 40% of HCC patients is a known poor prognostic sign with median survival rates of 2-4 months2,3,4. Many of these patients have hepatic artery to portal or hepatic vein shunts diagnosed at angiography when embolization is attempted. Arterioportal shunts (APS) are reported to occur in up to 62% of advanced HCC patients5. To our knowledge no reports of the prognostic significance of shunts in HCC patients are reported in the literature. We hypothesize that the presence of hepatic artery vascular shunts in advanced HCC is a poor prognostic sign with increased mortality despite locoregional embolization treatment. Methods: We report a small series of hepatic vascular shunt patients. Clinical status, preprocedure cross sectional and intra-procedural angiographic imaging was reviewed. The patients were monitored for overall mortality, and if possible for disease progression on follow up imaging. The Kaplan-Meier method was used to estimate survival. Results: Over a 28 month period, we had 50 patients with HCC treated with locoregional intraarterial therapy. 18% had a hepatic vascular shunt [arterioportal (n=7) or arteriovenous (n=3)]. 1 patient could not be treated due to the shunt, 5 were treated with DEBDOX, and 4 were treated with y-90. 66% of the vascular shunt population died with a median survival time of 1.7 months. Two patients remain alive (0.3 and 10.8 months living after 1st treatment, respectively). One patient was lost to follow up. Conclusions: Similar to portal vein invasion, non-operable HCC patients with hepatic vascular shunts have increased mortality despite locoregional therapy with median survival after the first treatment of 1.7 months.

P. Habibollahi1, T. Gade1, S. Hunt1, M.C. Soulen1, M.H. Levine2, G. Nadolski1. 1Department of Radiology, University of Pennsylvania, Philadelphia, PA; 2Department of Surgery, University of Pennsylvania, Philadelphia, PA.

J. Wildenberg2, T. Gade3, S. Hunt4, G. Nadolski5, M.C. Soulen1. University of Pennsylvania, Philadelphia, PA; 2University of Pennsylvania, Philadelphia, PA; 3University of Pennsylvania, Philadelphia, PA; 4University of Pennsylvania, Philadelphia, PA; 5 University of Pennsylvania, Philadelphia, PA.

Objective: Cirrhotomimetic (CMM) growth pattern is a rare variant of hepatocellular carcinoma (HCC) characterized by tumor nodules with growth that interdigitates within cirrhotic liver parenchyma. CMM HCCs are often discovered during pathological assessment of the explanted liver after transplantation (OLT), but may be suggested by MR imaging prior to neoadjuvant TACE. The present study examines differences in outcomes and response of CMM HCC to TACE. Methods: Retrospective review of all patients with pathologically proven CMM HCC (n=30) who underwent neoadjuvant TACE prior to OLT between 2007 and 2013 was performed. A control group of 46 patients with pathologically proven Non-CMM HCC who received neoadjuvant TACE prior to OLT during the same time period was used for comparison. Demographics, tumor response to TACE and overall survival following TACE and liver transplantation were recorded in both groups. Results: There was no significant difference in age at time of diagnosis between the CMM HCC and non-CMM HCC patients or gender. In the 30 patients with CMM HCC, 48 tumors were identified and treated while 64 HCCs were treated

Objective: Current guidelines recommend semiannual ultrasound (US) screening for hepatocellular carcinoma (HCC) in cirrhotics and some populations with chronic hepatitis B. Performance of liver US screening is dependent on both the operator as well as how the referring clinician interprets the results within the patient’s clinical context. This study compares the results of HCC screening US imaging before and after the implementation of a structured reporting initiative with standardization of both language and recommendations in the report to determine if the structured reporting improved compliance with screening guidelines. Methods: Screening US examinations of the liver for HCC performed in the two years following implementation of a structured reporting initiative were compared to those performed in the two years preceding implementation. A “non-negative” study was one in which a lesion was seen that was not definitively benign, or a study in which the liver was not sufficiently evaluated. For all “non-negative” studies, the patient’s history was reviewed to determine if they had cross-sectional imaging to complete the liver evaluation.

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Results: The treatment duration ranged from 20 to 80 minutes (mean : 30 minutes). A single insertion and 2 insertions of 3 electrodes occurred in 15 patients and 7 patients respectively. CT showed complete necrosis in 19/22 (86 %) patients. The remaining 3 patients underwent a second ablation session. No major complication occurred. Follow-up ranged from 6 to 57 months (mean 36 months). During follow-up, local recurrence occurred in 3/22 (14%) patients in 12 – 24 months. Distant new intrahepatic recurrences occurred in 15/22 (68%) within 6 - 30 months (mean 18 months). Recurrences were treated with locoregional therapy or chemotherapy. Ten patient died within 27 – 57 months after treatment, 6 because of tumor progression and 4 for non tumor-related reasons. Twelve patients are still alive. Conclusions: SC-RF proved to be safe in cirrhotic patients and effective for the treatment of medium- large HCC.

Poster 44: A Simple Yet Novel Technique to Mimic Selective Catheterization of Tumor Vessels During Chemoembolization When Challenging Anatomy is Encountered

Poster 46: Microwave Ablation of Large HCCs by Simultaneous Multiple Antennae Insertion: Long Term Follow-Up

T. Patel, K. Crawford, J.D. Prologo, D. Kies. Interventional Radiology, Emory University, Decatur, GA. Objective: The purpose of this exhibit is to describe a simple yet novel technique during drug-eluting bead chemoembolization (DEB TACE) where distal Gelfoam embolization (GE) of non-target vessels is performed to mimic selective catheterization of tumor vessels in cases where this is not feasible due to challenging hepatic arterial anatomy. Methods: DEB TACE is effective therapy for treating unresectable and medically inoperable HCC, or as a bridge to liver transplantation. Generally this is performed in a selective or superselective fashion to limit non-target embolization and side effects. Occasionally, patients have challenging anatomy where selective catheterization of the feeding vessel is not feasible. In these cases, bland embolization of non-target arterial branches with a temporary agent (Gelfoam) can be performed followed by proximal administration of drug-eluting beads in order to mimic selective administration. Results: This exhibit describes 2 patients with medically inoperable HCC treated with DEB TACE. In the 1st patient, angiography demonstrated a central mass that was supplied by multiple small perforating vessels off the right hepatic artery (RHA) whose small size and multiplicity made selective catheterization impossible. GE of the distal vascular bed was performed to redirect arterial flow into the small perforating vessels supplying the tumor. This was followed by proximal administration of DEBs into the right hepatic artery. In the 2nd patient, angiography demonstrated trifurcation of the RHA. The feeding vessel was the first branch of the trifurcation with the steepest angle of origin, and could not be catheterized. The other two non-target vessels were embolized with gelfoam followed by proximal administration of drug-eluting beads. Both patients were followed up at 4-6 weeks with MRI and labs to assess treatment response and liver function. Both patients had a complete response to therapy with no evidence of hepatic decompensation. Conclusions: When dealing with challenging hepatic arterial anatomy, distal GE of non-target vessels can be performed to mimic selective administration of drug-eluting beads with no significant risk of added toxicity. Poster 45: Radiofrequency Ablation with Switching Controller System of Medium Large Hepatocellular Carcinoma: 3 Year Follow-Up L. Tarantino2, P. Ambrosino4, P. Gallo1, P. Tarantino4, A. Nasto3. 1 Campus Biomedico University, Rome, Italy; 2Interventional Hepatology Unit, “A.Tortora” Oncology Hospital, Pagani, Italy; 3Oncological Surgery Department, “A.Tortora” Oncology Hospital, Pagani, Italy; 4Federico II University, Naples, Italy. Objective: We report 5 years follow-up results in the treatment of medium and large Hepatocellular Carcinoma (HCC) by multiple electrode insertion and switching controller Radiofrequency ablation (SC-RF) with intraoperative contrast enhanced Ultrasound (CEUS) control of efficacy. Methods: Between July 2009 and January 2015, 22 cirrhotics (62 – 84 years; 14 female; 13 Child-Pugh A and 9 B class) with a single HCC nodule (range, 3.0 - 5.8 cm; mean, 4.3 cm) were treated by US guided percutaneous SC-RF using a commercially available monopolar multiple-electrode radiofrequency ablation system based on switching between electrodes at impedance spikes (Cool-tip radiofrequency Switching Controller, Covidien). All treatments were performed in general anesthesia. In a single session 3 internally cooled electrodes were inserted into the tumor. Intraoperative CEUS (Sonovue, Bracco, Italy) and an additional electrode’s insertion was performed in case of residual viable tumor at CEUS. Definitive treatments’ efficacy was assessed by three-phase-enhanced- CT after 3 weeks. All patients were followed-up by US every 3 months and CT every 12 months.

L. Tarantino2, P. Ambrosino3, P. Gallo1, P. Tarantino4, A. Nasto5. 1 Campus Biomedico University, Rome, Italy; 2“A.Tortora” Oncology Hospital, Interventional Hepatology Unit, Pagani, Italy; 3Federico II University, Naples, Italy; 4Federico II University, Naples, Italy; 5“ A.Tortora” Oncology Hospital, Pagani, Italy. Objective: We report long term results of microwawe (MW) ablation with simultaneous insertion of multiple antennae in the treatment of large hepatocellular carcinoma (HCC). Methods: Between October 2008 and September 2013, 36 cirrhotics with a single HCC nodule >3 cm (range: 3.2-7.0 cm; mean: 4.4 cm) underwent MW ablation in a single session by simultaneous insertion of multiple 13-gauge-MW-antennae (VivaWave, Covidien, USA). After intra operative evaluation of efficacy with contrast enhanced ultrasound (CEUS), residual viable tumor was treated in the same session by reinsertion of 2-3 MW antennae. Efficacy of ablation was definitely assessed with three-phase computed tomography (CT) after one month, US every 3 months and CT every 12 months. Results: As scheduled according the tumor size, 10 and 18 patients were treated with a single insertion of 2 and 3 synchronous antennae, respectively. 8 patients were treated with 2 insertions of 3 antennae in the same session. Intraoperative CEUS showed residual tumor in 12 patients. Nine out of these patients underwent an additional insertion of 2 antennae and 3 patients of 3 antennae. Intraoperative CEUS at the end of the procedure showed complete necrosis in all patients. One month-CT showed complete necrosis in 33/36 patients. A severe hemoperitoneum, treated with blood transfusion, occurred in one patient after treatment. No other major complication occurred. Follow-up ranged from 18 to 78 months (mean: 42 months) and local recurrence occurred in 7 patients within 3 to 12 months (mean: 6 months). Recurrences in other liver segments occurred in 35/36 patients within 6 to 24 months (mean: 15 months). Extrahepatic metastasis were observed in 1 patient 24 months after treatment. Sixteen patients died within 18-60 months (mean: 36 months), for tumor progression in 11 cases, decompensation of cirrhosis in 4 cases, hemorrhagic stroke in 1 case. Twenty patients were alive at 18-78 months follow-up (mean: 42 months). Conclusions: Aggressive ablation of large HCC by simultaneous insertion of multiple MW antennae is safe and seems to result in patients’ survival comparing with surgery and small HCC ablation. Poster 47: Microwave Ablation of Large HCCs Using a New Device: A Case Series L. Tarantino2, P. Ambrosino3, P. Gallo1, P. Tarantino4, A. Nasto5. Campus Biomedico University, Rome, Italy; 2Interventional Hepatology Unit, “A.Tortora” Oncology Hospital, Pagani, Italy; 3Federico II University, Naples, Italy; 4Federico II University, Naples, Italy; 5 “A.Tortora” Oncology Hospital, Pagani, Pagani, Italy. 1

Objective: We evaluated a new device designed to achieve large volumes of necrosis in hepatocellular carcinoma (HCC) by synchronous insertion and activation of multiple Microwave (MW) antennae. Methods: Ten consecutive patients with a single large HCC nodule (diameter range: 3.5-6.5 cm; mean diameter: 4.6 cm) underwent ultrasound (US) guided percutaneous MW ablation by synchronous insertion of multiple MW antennae (SynchroWave 915 MHz antennas - MicroThermX® microwave ablation system, Terumo, Belgium, Europe). In general anesthesia, a single insertion of 2 antennae in 3 cases, and 3 antennae in 5 cases were performed. 2 insertions of 3 antennae in the same session were performed in 2 cases. Treatment efficacy was assessed by threephase contrast-enhanced computed tomography (CT) and bimonthly US follow-up. Results: Ten consecutive patients with a single large HCC nodule (diameter range: 3.5-6.5 cm; mean diameter: 4.6 cm) underwent ultrasound (US) guided percutaneous MW ablation by synchronous insertion of multiple MW antennae (SynchroWave 915 MHz antennas - MicroThermX® microwave ablation system, Terumo, Belgium, Europe). In general anesthesia, a single insertion of 2 antennae in 3 cases, and

WCIO Abstracts

Results: 607 patients had a screening US in the two years prior to the structured reporting initiative and 1385 after. The “non-negative” rate was 13.8% (n=84) before structured reporting and 13.0% after (n=180, p=0.610, Chi-square). Prior to structured reporting, 53 patients complied with guidelines and underwent subsequent cross-sectional imaging following a non-negative study (63.1%) compared to 107 patients following implementation of structured reports (58.8%, p=0.572, Chi-square). Conclusions: Overall, 39% of patients with non-negative screening US were not referred for additional diagnostic imaging. Implementation of a structured reporting initiative did not improve the rates of a non-negative screening US reports or compliance with recommended follow-up imaging. This suggests that for patients at risk for HCC the standardization of screening US reports has not impacted behavior for either the reading radiologist or referring clinician.

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3 antennae in 5 cases were performed. 2 insertions of 3 antennae in the same session were performed in 2 cases. Treatment efficacy was assessed by three-phase contrast-enhanced computed tomography (CT) and bimonthly US follow-up. Conclusions: The MicroThermX microwave ablation system seems an effective and relatively safe device for treatment of large HCC. Poster 48: Treatment Response In Glass Versus Resin Radioembolization of Hepatocellular Carcinoma

WCIO Abstracts

S. Iqbal, J. Vavricek, L. Rock, B. Jang, A. Robinson, S. Hunt, J. Wick, A. Rohr, T. James, S. DeBacker, J. Hill, T. Fahrbach, S. Lemons, P. Johnson, Z. Collins. Interventional Radiology, University of Kansas Medical Center, Kansas City, KS. Objective: To compare treatment response between glass and resin yttrium-90 (Y-90) microspheres radioembolization of hepatocellular carcinoma (HCC). Methods: A retrospective analysis was performed on 62 patients with hcc treated with glass or resin Y-90 radioembolization from 2008 to 2014 at an academic medical center. Up to two treated lesions per lobe were measured using cross-sectional imaging in the X, Y and Z planes at baseline and at 1, 3, 6, and 12 month intervals. Response was evaluated using the World Health Organization (WHO) and Response Evaluation Criteria in Solid Tumors 1.1 criteria Results: A total of 62 patients were evaluated with 40.3% (25) receiving resin and 59.7% (37) receiving glass particles. The majority were males (82.3%) with a mean age of 62.3 years (SD 8.2) and a mean MELD score of 9.9 (SD 3.1). Patients received an average radiation dose of 1.24 GBq (SD 0.25) with resin compared to 3.09 GBq (SD 1.56) with glass. Evaluation of tumor response using WHO criteria found 12.0% (3) of patients had a complete response (CR), 36.0% (9) had partial responses (PR), 52.0% (13) had stable disease (SD) and 0% had progressive disease (PD) when treated with resin particles and 2.7%(1) had CR, 35.1% (13) had PR, 45.9 % (17) had SD and 16.2 % (6) had PD when treated with glass particles. RECIST 1.1 response criteria demonstrated 12.0% (3) of patients had CR, 44.0% (11) had PR, 44.0% (11) had SD and 0% had PD when treated with resin and 2.7%(1) had CR, 27% (10) had PR, 54.1% (20) had SD and 16.2% (6) had PD when treated with glass (Table 1). Statistical testing with Fisher’s Exact test demonstrated a significant difference in tumor response by treatment type according to RECIST criteria (p=0.03), but not WHO criteria (p=0.12). Conclusions: Both glass and resin Y-90 microspheres are efficacious treatments for non-resectable HCC; however our study demonstrates that resin-based Y-90 therapy offers a higher rate of complete or partial response when compared to glass-based Y-90 therapy at nearly one third the radiation dose. Treatment Response

Poster 49: Hepatitis C Virus in 2016: A Disease Headed Towards Extinction? A. Baadh, A. Singh, J.C. Hoffmann. Radiology, Winthrop-University Hospital, Mineola, NY. Objective: To review Hepatitis C Virus (HCV), its importance and relevance to patients treated by Interventional Radiologists (IRs), and detail how newer medications used to treat HCV may impact IR practice. Methods: HCV is a cause of significant morbidity and mortality in the United States (US). As HCV is a major cause of cirrhosis and hepatocellular carcinoma (HCC) in the US, the approval of newer medications to treat HCV has the potential to dramatically impact and reduce HCV-related cirrhosis and HCC. IRs should be familiar with these new treatment options and thus understand how control and treatment of HCV may impact IR/IO practice. Results: HCV is reviewed in detail, including etiology, association with cirrhosis and HCC, and current medications available for HCV treatment. The relevant literature is reviewed, and HCV trends in the US are analyzed. The sales of newer antiviral medications used to treat HCV in the US are also analyzed, allowing for discussion about how interventional oncology practice may be affected in the coming years. In addition, cost analysis of these medicines is provided. This discussion will provide IRs with a better understanding of how HCV-related IR procedures may be impacted over the next 5-10 years. Conclusions: Newer oral medications now used in the US to treat HCV have great potential to decrease the rates of HCV-related HCC, and thus the number of interventional oncology procedures needed to treat these patients.

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Poster 50: Utilization of Quadrasphere Microspheres for Treatment of Hepatic Tumors with Same Day Discharge S. Mittal, A. Eweka, A. Baadh, A. Rahman, J.C. Hoffmann. Radiology, Winthrop-University Hospital, Mineola, NY. Objective: Historically, when performing transarterial chemoembolization, patients are hospitalized for at least one night for management of post-embolization syndrome (PES), which can include fever, abdominal pain, nausea, and vomiting. A larger number of patients are now treated with drug-eduling bead (DEB) chemoembolization. The purpose of this study is to report the safety and feasibility of same day discharge with the use of 30-60 micron spheres. Methods: A single institution retrospective analysis was performed of 27 consecutive DEB-TACE procedures utilizing 30-60 micron spheres (Quadrasphere Microspheres) from March 2013 through January 2015. Each vial of spheres was loaded with 50mg Doxorubicin. Some patients were planned for overnight admission before starting the procedure due to comorbidities and/or advanced disease. Other patients were treated with the primary intent of same day discharge. Records were reviewed to determine degree of post-embolization syndrome, pertinent lab values, Childs Pugh score, BCLC stage, ECOG status, admission status, and thirty-day readmission rates. Results: 27 DEB-TACE with 30-60 micron spheres were performed during the study period. Eighteen patients were hospitalized after DEB-TACE according to the attending physician’s plan before starting the procedure (deemed appropriate for admission due to comorbidities, labs, and/or performance status). Out of the 9 patients planned for same day discharge, all were discharged the same day with mild or no PES. One patient in this group was hospitalized and died within 30 days due to pneumonia and rapidly developing metastatic disease (BCLC C). No patients discharged on the same day or had overnight hospitalizations had severe PES. Conclusions: Patients treated with DEB-TACE using 30-60 micron spheres have low rates of clinically significant PES. Patients with PES typically have milder symptoms than patients treated with conventional chemoembolization. Most of the patients hospitalized after DEB-TACE could have been discharged the same day as the procedure. Same day discharge should be considered for patients undergoing DEB-TACE with 30-60 micron spheres, particularly BCLC Stage A and B disease. Poster 51: Assessment of Trans-Arterial Chemoembolization for Treatment of Mixed Cell Type HCC-Cholangiocarcinoma J. Groeniger, A.Y. Kim. Dept of Radiology, Medstar Georgetown University Hospital, Washington, DC. Objective: To assess the outcomes of patients with mixed cell type HCC-cholangiocarcinoma undergoing trans-arterial chemoembolization (TACE) Methods: Retrospective evaluation of 387 patients undergoing TACE from October 2008 to August 2015. Seven patients were identified as having mixed cell type HCC-cholangiocarcinoma on pathologic evaluation. Tumor response was assessed by both RECIST and mRECIST criteria. Results: Seven patients underwent a total of 14 chemoembolization sessions. All patients underwent DEB-TACE using a variety of bead types loaded with 50mg of Doxorubicin. Two patients also underwent single sessions of conventional TACE (cTACE) where 50mg of Doxorubicin, 50mg Cisplatin and 10mg of Adriamycin were infused along with 5 or 10cc of Ethiodol. A total of 11 lesions were treated with TACE. The median maximum tumor diameter was 2.2cm (range 1.0-4.1 cm). Follow up imaging was available in 6 patients with 10 lesions. One patient with a single lesion underwent transplantation prior to follow up imaging and was excluded from response evaluation. Based on mRECIST criteria, 6 lesions (60%) demonstrated complete response, 2 lesion (20%) demonstrated partial response and 2 lesions (20%) demonstrated stable disease after treatment. Based on RECIST criteria 2 lesions (20%) demonstrated partial response to treatment. The remaining 8 lesions (80%) demonstrated disease stability following TACE. Five of 7 patients underwent transplantation following TACE. One other patient underwent surgical resection. Degree of tumor necrosis on explants ranged from 10-95%. Microvascular invasion was identified in 2 patients on pathologic evaluation. Three patients from the cohort died at 13, 40 and 53 months following TACE. Both patients with microvascular invasion on pathologic evaluation died from metastatic disease. The third patient expired from respiratory failure 53 months post TACE. Four patients from the cohort are alive at time of analysis. The median survival from initial treatment to time of analysis is 30 months (4-54 months) for this cohort. Three patients have no evidence of disease. The fourth patient has biopsy confirmed metastatic disease. Conclusions: Trans-arterial chemoembolization is a valid treatment option for patients with mixed HCC-cholangiocarcinoma as a bridge to transplant. Patients demonstrating microvascular invasion on pathology may have a poorer prognosis.

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WCIO Abstracts

Poster 52: Cone Beam CT in the Treatment of Hepatocellular Carcinoma with Extrahepatic Collateral Supply S. McCabe1, Y. Zhang2, M. Lim2, S. Maddineni1. 1Interventional Radiology, New York Medical College, Waccabuc, NY; 2Radiology, Westchester Medical Center, Valhalla, NY.

including transarterial chemoembolization (TACE), HAIC with CDDP alone, and sorafenib are also available in Japan. However, it is controversial that which treatment is the best choice. The purpose of this study was to investigate the efficacy of HAIC with low-dose FP for locally advanced HCC in a single center experience. Methods: Low-dose FP consisted of a continuous arterial infusion of 5-FU (500 mg/body/day, 5 days/week, for the first 2 weeks) and CDDP (10 mg/body/day, 5 days/week, for the first 2 weeks). Then, 5-FU (1000 mg/m2, 5 hours) and CDDP (10 mg/body) were administered weekly or biweekly. Eighty patients (72 men and 8 women, median age; 68 years, Child-Pugh score A/B/C; 31/43/6, Barcelona Clinic Liver Cancer stage B/C/D; 24/50/6) with locally advanced HCC were treated by HAIC with low-dose FP from May 2006 to August 2015. Seventy-two patients had received prior treatments including TACE, HAIC with CDDP alone, and/or sorafenib. Time to treatment failure, median survival time (MST), tumor response and adverse reaction were investigated retrospectively. Results: Time to treatment failure was 1.1 months (range, 0.2-50) and MST was 6.3 months (range, 0.2-60). According to RECIST ver 1.1, objective overall response rate was 28.8% and disease control rate was 61.3% (CR/PR/SD/PD; 0/23/26/31) (Figure 1). There were no grades 3 or higher severe adverse reactions (CTCAE ver 4.0). The MST of PR+SD group (n=49) was much longer than that of PD group (n=31) (11.4 vs 2.7 months, p<0.001) (Figure 2). The MST in patients with prior treatments of HAIC with CDDP and/or sorafenib (n=49) was shorter than that in patients without them (n=31), but there was no statistical difference (4.2 vs 11.7 months, p=0.064) (Figure 2). Conclusions: Considering heavily prior treatment and limited liver functions in patients of this study, the response rate and disease control rate were acceptable. HAIC using low-dose FP for locally advanced HCC may be effective locoregional therapy.

Figure 1: A 70-year-old man with good PR Percutaneous placement of a port-catheter system for HAIC was performed (A). Pretreatment CT showed diffuse HCC in right lobe and portal vein tumor thrombus (B). Follow-up CT 4 months later showed tumor shrinkage (C).

a. Subselective hepatic angiogram demonstrates hypervascular segment VII HCC. b. Post TACE CBCT demonstrates a region of non-enhancement within the posterior aspect of tumor (red arrow), suggesting extra hepatic arterial supply. This defect was not visible angiographically. c. Right inferior phrenic arteriogram demonstrates tumor blush. d. Completion CBCT after emboilization via the right inferior phrenic artery (yellow arrow) confirms targeted treatment of the residual tumor (red arrow). Poster 53: Hepatic Arterial Infusion Chemotherapy with Low-Dose 5-Fluorouracil and Cisplatin for Advanced Hepatocellular Carcinoma H. Morinaga, Y. Sato, Y. Inaba, H. Yamaguchi, Y. Kinbara, T. Hasegawa, S. Murata, M. Kato, Y. Onoda, H. Yamaura. Department of Diagnostic and Interventional Radiology, Aichi Cancer Center Hospital, Nagoya, Japan. Objective: Hepatic arterial infusion chemotherapy (HAIC) with low-dose 5-fluorouracil (5-FU) and cisplatin (CDDP) (low-dose FP) is commonly used for locally advanced hepatocellular carcinoma (HCC) in Japan. Other treatment options

Figure 2: MST of PR+SD group and PD group (A), MST of prior treatments of HAIC with CDDP and/or sorafenib (B).

WCIO Abstracts

Objective: -Discuss the spectrum, prevalence and management of extrahepatic collateral arterial supply in Hepatocellular Carcinoma (HCC).-Discuss the role of C-arm cone beam CT (CBCT) in HCC embolization.-Illustrate potential advantages of CBCT in embolizing HCC with extrahepatic collateral supply. Methods: Between January 2014 and January 2015, 102 unique patients underwent 162 transarterial chemoembolization (TACE) or bland embolization (TAE) procedures for HCC at a single institution. Of these patients, 4 were treated via extrahepatic collateral arteries. Pre-procedural, procedural, and follow up imaging were evaluated. Results: Extrahepatic collateral supply was identified and treated in 4 out of 102 patients (3.9%), which is much less than that reported in literature (31-89%). Reported features of tumors with extrahepatic collateral supply coincident with our study population include large tumor size; exophytic architecture; bare area location; prior TACE/TAE; peripherally located residual viable tumor after previous TACE/ TAE; and incomplete tumor staining on angiography and CBCT. Culprit collateral supply arteries are also coincident with literature, with the most common being the right inferior phrenic. Followup imaging response correlated with post-TACE CBCT findings. Conclusions: Much of the literature on extrahepatic collateral supply to HCC is derived from Asian patient populations. Our study suggests incidence may be lower in Western patient populations. This discrepancy may be related to the high prevalence of hepatitis B-induced liver disease with associated larger tumor size in Asian patient populations; however, additional investigation with a higher powered study is warranted. Nonetheless, it is crucial for all interventionalists to be aware of the predisposing factors, treatment options, and specific treatment risks associated with extrahepatic collateral supply of HCC.CBCT has utility in intraprocedural tumor localization, planning, and assessment of treatment efficacy after embolization. Completion CBCT may demonstrate angiographically occult regions of untreated tumor supplied by unsuspected extrahepatic collateral supply. In addition, it can confirm complete tumor coverage after embolization via extrahepatic feeding arteries. Here we provide a review of the literature and a case based discussion of the utilization of cone beam CT in the setting of HCC with extrahepatic collateral supply.

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Poster 54: Percutaneous Microwave Ablation of Hepatic Tumors Adjacent to the Inferior Vena Cava: Evaluation of Heat-Sink Effect

WCIO Abstracts

S.H. Allgeier1, J.M. Willatt2, B.S. Majdalany1, W.A. Saad1. 1Department of Radiology, University of Michigan Medical Center, Ypsilanti, MI; 2 Department of Radiology, University of Michigan Medical Center and VA Ann Arbor Healthcare System, Ann Arbor, MI. Objective: To evaluate whether percutaneous microwave tumor ablation may be used to effectively treat hepatocellular carcinomas immediately adjacent to the inferior vena cava (IVC), to evaluate the heat-sink effect of the IVC on the tumor ablation zone, and to assess treatment-related damage to the IVC. Methods: Microwave ablation of tumors adjacent to the IVC in the caudate, right, and left hepatic lobes was performed using a 2.45-MHz generator (AMICA-GEN, HS Hospital Service SpA, Aprilia, Italy) delivering energy through a 14-gauge internally cooled coaxial antenna (AMICA PROBE, HS Hospital Service SpA, Aprilia, Italy), featuring a miniaturized quarter wave impedance transformer (minichoke) for reflected wave confinement. Routine follow up imaging was performed with liver MRI or 3-phase liver CT to evaluate for residual tumor at the ablation site and to assess for IVC thrombus or stricture. Results: Microwave ablation has become well established as a treatment modality for early stage hepatocellular carcinoma. This technique, which involves percutaneous image-guided placement of an antenna into the target lesion and subsequent intra-lesional heat generation through electromagnetic wave agitation of polar molecules, results in tumor necrosis with limited damage to surrounding normal tissue. Previous studies have reported decreased efficacy of percutaneous ablative techniques adjacent to vascular structures greater than 3 mm in diameter due to the heat-sink effect, whereby generated heat is dissipated by adjacent flowing blood. We describe a series of nine cases in which single-antenna percutaneous microwave ablation was performed on tumors adjacent to the IVC, four in the caudate lobe, four in the right hepatic lobe, and one in the left hepatic lobe, without distortion of the expected ablation zone to suggest any appreciable heat-sink effect. Undistorted ellipsoid ablation zones were achieved which fully treated the targeted tumors, and there was no evidence of adverse effect to the IVC. Conclusions: Percutaneous microwave tumor ablation is effective in generating a uniform ellipsoid ablation zone even when the targeted tumor is immediately adjacent to the IVC. No appreciable heat-sink effect occurred due to blood flow in the IVC, and there was no evidence of treatment-related damage to the IVC such as caval stenosis or thrombosis. Microwave ablation may therefore be superior to other ablation methods such as radiofrequency ablation in the treatment of tumors adjacent to large blood vessels. Poster 55: PV Thrombus Percutaneous Management by Endoportal RFA and Stenting as a Bridge to Curative Treatment of HCC M. Mizandari1, N. Habib2, T. Azrumelashvili1. 1Tbilisi State Medical University, Tbilisi, Georgia; 2surgery and oncology, Imperial College London, London, United Kingdom. Objective: HCC complication by PV thrombosis (PVT) is the frequent cause of patient excluding from the curative treatment candidates list; paper presents the novel technique of PV thrombus recanalization Methods: 14 patients underwent percutaneous endoluminal RF treatment attempt. Peripheral to the thrombus, patent PV tributary puncture is performed under US guidance; manipulation by 5 Fr diameter guiding catheter is used to conduct the guidewire across the blocked segment and portography is performed. 10 to 15 Watts power was applied for 2 minutes using bipolar endoluminal RF device (Habib™ EndoHPB, EMcision Ltd., London, UK), placed in PV blocked segment according the guidewire. The number of RF application sessions depended on the extent of the tumour thrombus as shown on portography performed by guiding catheter tip positioning “above” and “below” the PV thrombus. Immediately after RF application self-expanding 14 mm diameter vascular stent was positioned. This was followed by portography to confirm the PV patency restoration. Procedure is completed by procedure track embolisation by coil or by track RF ablation using the same RF catheter. Results: The procedure was completed in 10 (71.4%) cases; in 3 (21.5%) cases we could not conduct the wire across the thrombus; in the rest 1 (7.1%) case the thrombus was traversed by the wire but we failed to conduct the RF device and procedure was completed by stenting. Portal vein obstructed segment showed the restored blood flow in all completed cases as documented by postprocedure portography, follow-up Doppler and CT studies; this resulted in liver function improvement in 6 (60.0%) of procedure technical success cases. Recanalized PV patency varied from 3 weeks to 22 months; in 3 cases patients underwent successful TACE procedure after PV recanalization. Conclusions: PV thrombus percutaneous recanalization by endoportal RFA with subsequent stenting is an effective technique and should be suggested as a possible treatment option of HCC patients with PVT. In cases of procedure clinical success patient may become eligible for further curative treatment

Stent is released, portography shows the restored patency Poster 56: Long Term Outcomes with Multidisciplinary Management of Hepatic Adenomatosis S. Reddy3, T. Gade2, G. Nadolski4, M.C. Soulen1, S. Hunt5. 1University of Pennsylvania, Philadelphia, PA; 2Interventional Radiology, University of Pennsylvania, Philadelphia, PA; 3Interventional Radiology, University of Pennsylvania, Philadelphia, PA; 4Interventional Radiology, University of Pennsylvania, Philadelphia, PA; 5 Interventional Radiology, University of Pennsylvania, Philadelphia, PA. Objective: To describe long term outcomes following a multidisciplinary approach for the management of hepatic adenomatosis. Methods: A retrospective review of our IR database from January 2004- January 2010 was performed under IRB approval. Twenty-two transarterial embolization (TAE) procedures for 16 patients with hepatic adenomas were identified. All patients were women (mean age 37.5), with a high incidence of obesity (81%), oral contraceptive use (69%), and clinical evidence of estrogenic dysfunction (38%). Thirteen patients had pathologic confirmation, while three had intratumoral hemorrhage with MR findings consistent with adenomatosis. Segmental or lobar embolization was performed. Post-embolization assessment was performed according to RECIST and mRECIST criteria.

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Poster 57: A Comparison of Tumor and Ablation Dimensions after Radiofrequency (RF) and Microwave (MW) Ablation of Small Hepatocellular Carcinoma (HCC) at a Single Center E. Nocerino1, T. Ziemlewicz2, F. Lee2, C. Brace2. 1Radiology, Università Degli Studi di Milano, Milan, Italy; 2Radiology, University of Wisconsin School of Medicine and public health, Madison, WI. Objective: Recent studies show a higher incidence of local tumor progression (LTP) in patients with small HCC treated by RF ablation compared to those treated with MW ablation. The aim of this study was to evaluate whether each tumor population was treated similarly and to help determine possible explanations for the difference in LTP rates. Methods: This retrospective study included 35 HCC in 27 patients treated by RF ablation, and 134 HCC in 106 patients treated by MW ablation. Patients who underwent prior treatment with TACE or ablation, or HCC treated with more than two electrodes/antennas were excluded from our search. For both tumor and ablation zones, three orthogonal diameters were measured from the available contrast-enhanced CT or MRI performed pre and post-ablation. Tumor and ablation volumes were calculated by an ellipsoidal assumption. Incidents of local tumor progression (LTP) were also collected. Tumor diameters, ablation diameters, the difference between ablation and tumor volume and the differences between minimum diameter ablation and minimum diameter tumor were compared between RF and MW ablation groups using Student’s t-test. Fisher’s exact test was used to compare LTP between RF and MW groups. Results: There were no significant differences in tumor diameters or volumes between RF and MW ablation groups. Mean HCC maximum diameter was 20.1 mm in the RF group (range 7-34 mm) and 20.4 mm in the MW group (11-37 mm; p=0.810). Mean HCC volume was 3.9 cm3 the RF group (0.15-14.6 cm3) and 3.8 cm3 in the MW group (0.4-19.5 cm3; p=0.969). Similarly, there were no significant differences in ablation diameters or volumes. Mean ablation maximum diameter was 41.8 mm in the RF group (range 25.7-67.6 mm) and 38.7 mm in the MW group (22.2-70.0 mm; p=0.0593). Mean ablation volume was 24.4 cm3 the RF group (4.9-49.0 cm3) and 20.8 cm3 in the MW group (4-76 cm3; p=0.155). Furthermore no significant differences in the ablation zone and tumor volume and the minimum diameter ablation and minimun diameter tumor difference were found between two groups (p=0.1174, p=0.1640 respectively). As noted in previous analyses, the rate of LTP was higher in the RF group (14.2%) compared to the MW group (4.5%; p= 0.051). Conclusions: The higher incidence of LTP after RF ablation compared to MW ablation in the treatment of small HCC is not ascribed to a difference in ablation volumes. Other mechanisms such as tissue contraction may play a role. Poster 58: Portal Vein Embolization in Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis R.A. Charalel1, A. Giambrone2, J. Jo1, L. Tmanova3, D.C. Madoff1. 1 Radiology, NewYork-Presbyterian-Weill Cornell Medical Center, New York, NY; 2Healthcare Policy and Research, Division of Biostatistics and Epidemiology, Weill Cornell Medical College, New York, NY; 3 Weill Cornell Medical College, New York, NY. Objective: Portal vein embolization (PVE) outcome data is limited by mixed study populations including multiple primary and secondary liver cancers, liver disease severities and various methods of PVE and CT volumetry. PVE outcome data specific to the hepatocellular carcinoma (HCC) population is particularly limited. Here, for the first time, we performed a systematic review and meta-analysis summarizing available evidence, specific to this population. Methods: We performed a comprehensive literature search of all reported PVE outcomes in HCC subjects. We included cohort studies, which examined the future liver remnant (FLR) percent hypertrophy, proportion post-hepatectomy and/or proportion with major complications following PVE. Three separate meta-analyses using

random-effects models with assessment of study heterogeneity and publication bias were performed for FLR mean percent hypertrophy, hepatectomy rate and major complication rate. Results: Of the 7072 articles screened, 15 articles with a total of 416 subjects met eligibility for systematic review. Based on the 15 eligible studies with FLR mean percent hypertrophy data and hepatectomy data, the random effects pooled estimate of FLR mean percent hypertrophy was 32.5% (SD 13.3%, Q=154.2, p=<0.0001) over a mean interval of 30.3 days (SD 21.9 days) and the pooled proportion of subjects who received hepatectomy was 89.4% (95% confidence interval (CI): 81.3% to 95.4%, Q=77.5, p=<0.0001). Of the 9 eligible studies with major complications data, the pooled proportion of subjects who had a major complication attributable to portal vein embolization was 3.3% (95% CI: 0.9% to 7.2%, Q=14.7, p=0.06). Conclusions: PVE in HCC subjects has a low major complication rate and a high rate of successful hepatectomy. However, analysis of pre-surgical methods to induce liver hypertrophy including PVE, portal vein ligation and radiation lobectomy remains limited by heterogeneous study populations and methods. Future controlled prospective studies would be beneficial to allow comparison between these varied methods. Nonetheless, PVE in the setting of HCC is clearly a safe and effective method to induce liver hypertrophy and successfully bridge to hepatectomy. Poster 59: Dose Determination of Doxorubicin Administered during DEB-TACE by Spectral Measurements S.B. White, V. Gogineni, D. Park, W. Lea, E. Hohenwalter, S. Tutton, W. Rilling. Radiology, Medical College of Wisconsin, Milwaukee, WI. Objective: DEB-TACE is now a widely utilized treatment for primary and secondary liver cancer; however, recent studies suggest that this new modality confers an increased risk of hepatic toxicity. In medical oncology, it is well known that toxicities are related to the dose administered to the patient. Interventional oncology studies currently only report the dose of the DEBs intended for use and not the actual amount of drug delivered. The purpose of this study is to determine the doxorubicin dose delivered to a patient during DEB-TACE, by extrapolating from the residual concentration from unused beads. Methods: In order to determine the initial dose of the drug, the loading efficiency at the local pharmacy was determined by loading beads with Doxorubicin 50 mg per their standard protocol at three different time points. UV/Vis/Spect was performed on the supernatant remaining after drug loading in triplicate and loading efficiency was determined. To determine the dose delivered to the patient, at the conclusion of the DEB-TACE procedures, all of the syringes used for delivery of the beads were collected (including the syringe from pharmacy). All of the syringes were rinsed with sterile water and collected into a single syringe and the residual volume was measured. The drug was then eluted from the beads and the drug concentrations were determined using UV/Vis/NIR spectrophotometry. A calibration curve was also obtained by plotting known concentrations against the emission. Results: Of the 2 ml of beads provided for loading with doxorubicin, an average of 1.3mL of beads were recovered after loading. However, spectral measurements using a reference curve revealed that the binding efficiency of the beads was more than 99.8% leaving behind <0.1mg unbound drug. Among the 6 patient samples after DEB-TACE procedures tested thus far, volume of the residual beads ranged from 0.20 mL- 1.25 mL of beads with a median of 0.9 mL. Spectral analysis of the same samples revealed that up to 88% (7.6mg-43.2mg) of Doxorubicin with a median value of 32.36 mg was left undelivered in the syringes. Conclusions: We were able to successfully quantitate the residual amount of doxorubicin both by volume and spectral analyses. Although there is a marked loss of beads during drug loading in the pharmacy, the remaining beads retain nearly the entire dose of drug, indicating that the amount of drug to the volume of beads ratio is higher than the manufacturer’s suggested the ratio. Furthermore, assessment of DEBTACE induced hepatotoxicity should incorporate the actual quantity of drug delivered to predict outcomes, as there is significant proportion of residual drug. Poster 60: Does Pulsatile Catheter Injection Result in Better Transarterial Tumor Perfusion than Steady Continuous Injection? M. Moussa1, M. Patel1, M. Beheshti2. 1Radiology, University of Arkansas for Medical Sciences, Little rock, AR; 2Radiology, VA, Little rock, AR. Objective: To compare tumor perfusion when an intrahepatic catheter is injected with pulsatile injection (PI) versus industry recommended (current standard) steady continuous injection (SCI). Methods: Eight patients undergoing standard Y90 radioembolization work up were enrolled. The mean age was 61.3 years (range 56-69 years). Hepatic CT angiography was performed through a parked catheter in the appropriate segmental artery. Images were acquired in pre-contrast phase, SCI arterial phase and PI arterial phase. Contrast was hand injected in all phases. Images were analyzed by identifying three to five 1 cm2 regions of interest in viable tumor and surrounding normal appearing liver. Collected

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Results: Eleven patients (69%) had five or more adenomas and 15 (94%) presented with at least one adenoma >45 mm. Indications for TAE included intratumoral hemorrhage (n=9), lesion size (n=4), and elevated LFTs (n=3). TAE was the sole treatment for 7 patients, while 9 patients had a combination of TAE and surgery. Thirteen patients (81%) had imaging follow-up after embolization for a median of 54.5 months. Overall, 69% (n=9) met RECIST criteria for partial response with mean reduction in baseline sum longest diameter of 56% (p=0.02). Of the 15 target lesions considered “surgical” due to size (>45 mm), 60% were successfully downsized. One patient (6 %) demonstrated initial treatment response however had malignant transformation six years later to HCC resulting in her death. Conclusions: Hepatic adenomatosis holds potential for morbidity secondary to tumoral hemorrhage and rare malignant transformation. Embolization offers a safe and effective therapy, particularly in cases of multifocal disease. A coordinated approach with surgical and interventional treatment planning is likely to offer the best therapeutic option for most patients. Rare malignant transformation necessitates long-term imaging follow-up.

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HU values were used to calculate difference in mean tumor enhancement and tumor to liver (T/L) enhancement ratio. Results: All patients demonstrated significantly improved mean tumor enhancement with PI vs. SCI (184 r 74 HU vs. 134 r 51 HU), p value < 0.002. Similarly, 6 out of 8 patients demonstrated improved T/L enhancement ratios when contrast was injected using PI vs. SCI (1.6 r 0.6 vs. 1.3 r 0.5), P value < 0.05. Conclusions: Pulsatile transarterial catheter injection improves tumor perfusion and minimizes normal parenchymal perfusion when compared to the steady continuous injection technique. Current glass microsphere Y90 manufacture recommendations specify steady continuous injection. Our observations suggest that current manufacture recommendations may preclude optimal Y90 microsphere delivery.

Poster 62: Transcatheter Arterial Chemoembolization Combined with Radiofrequency Ablation Therapy Versus Repeat Hepatectomy for Recurrent Hepatocellular Carcinoma: A Retrospective study Z. Peng1, K. Ming2. 1the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China; 2The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.

Poster 61: Radioembolization with Yttrium-90 Resin Microspheres in Patients with Hepatocellular Carcinoma and Portal Vein Tumor Thrombosis Associated with Arterioportal Shunt N. Pinjaroen. Interventional Radiology Unit, Radiology Department, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. Objective: Transarterialradioembolization (TARE) with Y90 microspheses is a promising treatment option for HCC with portal vein tumor thrombosis (PVTT). PVTT is frequently associated with arterioportal (AP) shunt, which precludes transarterial chemoembolization (TACE) because drugs can pass through the AP shunt potentially compromising portal blood flow and resulting in extensive liver ischemia. On the contrary, Y90 microspheres size is much smaller and has less embolic effect than lipiodol droplet which is used for TACE. However, Y90 microspheres that pass through AP shunt may reduce radiation dose deposition within the tumor and adversely increase radiation dose deposition in the normal liver. This study aims to evaluate safety and treatment outcome of Y90 in HCC with PVTT and AP shunt. Methods: We retrospectively reviewed medical records of 10 HCC patients with PVTT who underwent hepatic arterial mapping with 99mTc-MAA administration between Aug 2014 to Aug 2015. Of these, 7 patients received TARE with Y90 resin microspheres. Patients demographic data, cross-sectional imaging, angiographic findings, lung shunt fraction (LSF) study, SPECT/CT, pre- and post-treatment LFT and adverse effects were reviewed. Results: All patients had cirrhosis Child-Pugh class A. Mean tumor size was 7.7r3.6 cm (range, 2-12 cm). Six (60%) patients had multifocal lesions. Four (40%) patients had bilobar disease. Levels of PVTT invasion included first order branch (60%) and main PV (40%). Two patients had hepatic vein invasion and one patient had both hepatic vein and IVC invasion. AP shunt was found on angiography in 7 patients (70%). Mean LSF was 10r7.7% (range, 3.3-30%). Three patients were not eligible for TARE due to LSF>20% (n=1), uncorrectable gastric uptake (n=1) and dominant uptake in normal liver from SPECT/CT (n=1). Seven patients received TARE with Y90 for segmental (n=2), lobar (n=4) and sequential bilobar (n=1) treatment. Five (71%) patients with AP shunt showed contrast reflux into ipsilateral PV (n=3), contralateral PV (n=1) and main PV (n=1). However, all of these showed dominant radioactivity uptake within the tumorous area or the target lobe. Mean target dose was 105r35Gy (range, 50-155 Gy). Response rate (71%) based on EASL criteria included CR (n=1) and PR (n=4). Other two patients had stable disease. Mean follow-up time was 7.1r3.7 months (range, 2-11 months). Grade 1 biochemistry toxicities (based on CTCAE v4.0) was found in 4 patients (57%). One patient had grade 4 bilirubin toxicity, grade 2 AST/ALT toxicity and died 5 months after treatment, which may related to herb-induced liver injury. One patient died 2 months after TARE due to cerebrovascular disease. Median TTP (n=4) was 6.5 months (range, 4-8 months). Conclusions: HCC with PVTT is highly associated with AP shunt, which should not preclude TARE with Y90 resin microspheres if majority of the given dose deposits in the tumorous area or the target lobe. Hepatic arterial mapping and 99mTc-MAA SPECT/CT should be carefully reviewed for treatment planning and dosimetry in individual patient.

Objective: To compare the safety and effects of transcatheter arterial chemoembolization (TACE) plus radiofrequency ablation (RFA) with those of repeat hepatectomy in the treatment of recurrent hepatocellular carcinoma (HCC). Methods: From September 2008 to, June 2015, 123 patients with recurrent HCC measuring 5.0 cm in diameter or smaller were included in this study. These patients were divided into two groups: 70 patients with 78 tumors were treated with RFA followed by TACE(the TACE-RFA group) and 53 patients with 58 tumors were treated by repeat hepatectomy (the resection group). The survival curves were constructed with the Kaplan-Meier method and compared by using the log-rank test. Results: At a median follow-up of 54 months, 37 patients in the TACE-RFA group and 29 patients in the resection group had died. Totally, 41 patients and 38 patients had developed recurrence in the TACE-RFA group and resection group, respectively. The 1-, 3-, and 5-year overall survivals for the TACE-RFA group and the resection group were 87.1 %, 62.3 %, and 48.1 % and 84.9 %, 65.8%, and 47.1 %, respectively (p=0.737). The corresponding recurrence-free survivals were 65.7%, 43.2%, and 39.9% and 56.6%, 33.7%, and 26.8%, respectively (p=0.272). Major complications such as liver failure, gastrointestinal hemorrhage, moderate/severe ascites happened more often after repeat hepatectomy than TACE-RFA (p=0.046, 0.046, 0.023 respectively), while vomiting was significantly more often after TACE-RFA than repeat hepatectomy (p=0.001). A multivariate regression analysis revealed that AFP level was significant prognostic factors for overall survival, whereas interval between initial treatment and tumor recurrence was significant prognostic factor for recurrence-free survival. Conclusions: TACE combined with RFA is an efficient and safe treatment that provides overall survival rates similar to those achieved with repeat hepatectomy in the treatment of recurrent small HCC. Poster 63: Salvage Resection for Recurrent or Metastatic Hepatocellular Carcinoma after Percutaneous Ablation Therapy: Old Therapy Served as New Strategy K. Ming, Z. Peng. the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. Objective: To retrospectively evaluate the efficacy and safety of salvage resection for recurrence of hepatocellular carcinoma (HCC) after initial percutaneous ablation therapy (PAT). Methods: From September 2006 to September 2013, 50 consecutive patients who received salvage resection for recurrent or metastatic HCC undergone initial PAT were enrolled. Salvage resection was performed when (a) repeated PAT failed (n=29); (b) inapplicable for repeated PAT because of high risk tumor location (n=2); (c) multiple intrahepatic recurrences within one lobe (n=6); (d) solitary extrahepatic metastasis within abdominal cavity (n=10); (e) major PAT-related complications appeared (n=3). Safety and efficacy of salvage resection for these patients were analyzed. Results: No treatment-related death occurred. Curative outcome was achieved in all the patients. Postoperative follow-up time ranged from 1 to 69 months. The disease-free survival was 38.6% at 1 year and 12.1% at 3 years after salvage resection. The median overall survival after salvage resection was 40 months, and the 1-, 3-, 5-year overall survival rate after salvage resection was 85.2%, 46.4% and 34.8%, respectively. Conclusions: Salvage resection is an effective and safe method for recurrent or metastatic HCC undergone initial PAT treatment, especially for those when repeated PAT inapplicable or failed.

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Poster 64: Local Therapy Combined with Sorafenib the Treatment of Advanced Recurrent Hepatocellular Carcinoma K. Ming, Z. Peng. the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.

a venous lake. A similar phenomenon of large arterial to portal fistulas has been described after chemoembolization with conventional TACE, but to our knowledge a hepatic arterial to hepatic venous fistula has not been described during TACE with Doxorubicin DEBs. Results: In several patients with hypervascular encapsulated HCC fed by a solitary enlarged vessel, we have identified a change in the vascular pattern during DEB-TACE. These cases originally demonstrate tumor hypervascularity without a macroscopically identifiably arteriovenous shunt. After the predictable embolization changes and staining of the tumor is identified, we have found that a large channel can form between an arterial feeder and the hepatic vein with pooling of contrast and slow but complete washout. The ideal end point for treatment of hypervascular HCC with DEB-TACE has yet to be firmly established. In situations where stagnation of the supplying artery is desired for DEB -TACE, this newly described phenomenon creates a situation where arterial flow does not slow down. It is important to be aware of this potential change in tumoral vascularity. We have found it necessary to change the procedure at this point as the shunting of doxorubicin eluting beads into the venous system can result in non-target embolization. Conclusions: Large caliber arteriovenous shunting occuring during TACE is a new potential complication of DEB-TACE. This potential complication is important to recognize to avoid non-target embolization.

Poster 65: Safety and Feasibility of Transarterial Chemoembolization for Hepatocellular Carcinoma Using an Antireflux Catheter M.C. O’Dell, B. Liu, J. Limback, T. Ward, F. Contreras. Diagnostic Radiology, Florida Hospital, Windermere, FL. Objective: Transarterial chemoembolization (TACE) is an effective treatment alternative in cases of intermediate or advanced hepatocellular carcinoma (HCC). Many different sets of equipment and techniques have been introduced to increase the safety and effectiveness of this procedure. The purpose of our study is to investigate the safety, effectiveness and feasibility of performing TACE with the Surefire Precision antireflux catheter (Surefire Medical, Inc., Westminster, Colorado). Methods: A single institution retrospective analysis was performed in 8 consecutive patients with unresectable HCC who underwent TACE with the Surefire Precision anterior reflux catheter over a 3-month period. All procedures were performed using 30-60 Pm drug-eluting beads loaded with 50mg of doxorubicin. All patient’s received routine clinical, laboratory and imaging follow-up to assess for treatment efficacy and complications as described in the SIR guidelines. Imaging was obtained prior to and 1 month following TACE to assess for treatment effectiveness. Viable tumor is described as the sum of two diameters of the arterially enhancing tumor component, as outlined in the modified Response Evaluation Criteria In Solid Tumors (mRECIST) criteria for HCC. Results: Our study population (N = 8) included 5 males and 3 females with a mean age of 62 years (range, 57-66 years). Four patients were Child-Pugh class A, and four were class B. A total of 13 tumors were treated with a mean initial maximum diameter of 3.62 cm (SD = 1.53). Per mRECIST criteria, there were a total of 2 complete responses (CR), 7 partial responses (PR), and 4 stable responses (SR). The overall total response rate (CR+PR) was 69%. No significant adverse events were recorded in this patient population. Conclusions: Transarterial chemoembolization using the Surefire Precision antireflux catheter is considered safe and effective in our study population given the treatment success rate and the absence of complications. Poster 66: Tumoral Vascularity Alteration During a Transarterial Chemoembolization (TACE) with Doxorubicine Drug-Eluting Beads (DEBTACE) with the Formation of a Large Caliber Arteriovenous Shunt and Venous Lake S. Gueyikian, S. Hiremath, B. Bodager. Interventional Radiology, Aurora St. Luke’s Medical Center, Milwaukee, WI. Objective: The objectives of this educational exhibit are to describe a novel phenomenon identified during TACE with Doxorubicin (DEBs) during TACE (DEB-TACE). Methods: Locoregional treatment of hepatocellular carcinoma with Doxorubicin DEBs via TACE is well-documented in the literature. Recently, our institution has identified a novel phenomenon occurring during TACE with Doxorubicin DEBs. We have found that during chemoembolization, the tumoral perfusion pattern can rarely transform from a hypervascular mass to a large arteriovenous shunt with

DSA angiogram of right hepatic 7cm HCC showing hypervascular tumoral pattern without shunt or pooling of contrast.

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Objective: To retrospectively evaluate the clinical efficacy of local therapy combined with sorafenib in the treatment for advanced initial recurrent hepatocellular carcinoma (HCC) after liver resection Methods: From July 2009 to October 2014, a total of 108 consecutive patients administered with radiofrequency ablation (RFA) combined with sorafenib (RFASorafenib group, n = 55) or transarterial chemoembolization (TACE) combined with sorafenib (TACE-Sorafenib group, n = 53) for advanced initial recurrent HCC after liver resection were enrolled. The treatment-related adverse effects, treatment efficacy of these patients were evaluated and compared between these two groups. Results: The most common treatment-related adverse events were hand-foot skin reaction (108/108, 100%) and diarrhea (101/108, 93.5%) for all patients. Seventy-eight patients (78/108, 72.2%) were dead due to tumor progression during follow up. The median OS was 14.0 months for all patients. The 1-, 2-, and 3-year overall survival (OS) rates were 63.8%, 34.3%, and 30.9% for RFA-Sorafenib group, and were 53.3%, 22.8%, and 11.8% for TACE-Sorafenib group, respectively (P =0.024). Among patients with d 3 intrahepatic tumors (n = 50), RFA-Sorafenib group (n = 37) showed better survival outcomes than TACE-Sorafenib group (n = 13) (p = 0.004). Multivariate analysis indicated that AFP distribution (p = 0.036) and treatment group (p = 0.028) were the significant prognostic factors for OS after treatment. Conclusions: Combined local therapy and sorafenib is an acceptable treatment for patients with advanced initial recurrent HCC after liver resection. RFA-sorafenib is superior to TACE-sorafenib and may improve survivals, especially in patients with d 3 intrahepatic tumors.

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Poster 68: Safety and Toxicity of Resin Y-90 Radioembolization in the Treatment of BCLC Stage C Hepatocellular Carcinoma: A SingleInstitution Experience

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A. Miller1, K. Unger2, A.Y. Kim1. 1Department of Radiology, Medstar Georgetown University Hospital, Washington, DC; 2Radiation Oncology, Medstar Georgetown University Hospital, Washington, DC.

After infusion of 50 mg of Doxorubicin DEBS, there is a significant change in the vascular pattern. There is a large venous pool and continual arteriovenous shunt. Poster 67: Feasibility of Outpatient Transarterial Chemoembolization with Drug-Eluting Beads (DEB TACE) for Treatment of Hepatocellular Carcinoma (HCC) Using a Novel Premedication Regimen C. Young1, A. Makrmalla1, M. Smetts1, J. Jeong1, O. Olowokure3, S. Shah2, C. Schatzman1, C. Carr1, R. Ristagno1. 1Radiology, University of Cincinnati, Cincinnati, OH; 2Surgery, University of Cincinnati, Cincinnati, OH; 3Hematology and Oncology, University of Cincinnati, Cincinnati, OH. Objective: DEB TACE is a widely used locoregional therapy for HCC. Standard practice is to hospitalize these patients for 1-2 days for observation and symptomatic control of postembolization syndrome (PES). We present our experience of performing outpatient DEB TACE with a novel premedication regimen. Methods: This is a single center, retrospective review of all HCC patients who underwent DEB TACE over a 23 month period. 113 consecutive procedures in 71 patients were reviewed. All patients received premedication with dexamethasone 8 mg IV and fosaprepitant 150 mg IV. Periprocedural IV antiemetics and analgesics were also provided as needed. Discharge medications included oxycodone, promethazine and an antibiotic. The endpoint of the study was admission for PES within 7 days of the procedure. Results: Of the 113 DEB TACE procedures, 5 patients were admitted for PES (4.4%). 99 patients were successfully treated as outpatients. 9 patients were hospitalized or seen in the ED for reasons unrelated to PES (social reasons, altered mental status, groin hematoma, or other medical reasons). Mean doxorubicin dose was 43.6 mg (range 5-100 mg). Microsphere sizes were 70-150P(30.1%), 100-300P(59.3%) and 300-500P(10.6%). Conclusions: Outpatient DEB TACE after premedication with dexamethasone and fosaprepitant is feasible with low incidence of admission for PES. Results

Objective: The purpose of this study was to evaluate the toxicity of resin Y-90 radioembolization in patients with BCLC stage C hepatocellular carcinoma treated at our institution. Methods: A retrospective review was completed of all patients with BCLC stage C HCC treated with resin microsphere Y-90 at our institution over a 33-month period (1/2012 – 9/2014). Data was collected from post-treatment clinical notes, including office visits and emergency room encounters, as well as phone encounters. Treatment toxicities were defined as any adverse event occurring within 60 days following selective internal radiotherapy (SIRT). Toxicities were graded on a standardized scale for all patients. Mortality data was also collected. Results: A total of 24 patients (18 males and 6 females) were evauated. The mean age was 62 years. All patients had unresectable HCC and ECOG > 3 [19 patients (79%) with ECOG 1, one patient (4%) with ECOG 2]. Twelve patients had portal vein thrombosis on baseline imaging (50%), with involvement of the main (n = 4), lobar (n = 5) and segmental/subsegmental (n = 3) portal veinsEighteen patients were treated with a single SIRT (75%), while the remaining 6 patients were treated with two SIRTs. Nineteen of 24 patients (79%) experienced a post-treatment toxicity. The most common toxicities (affecting > 5% of treated patients) were: fatigue (58%), pain (46%), ascites (33%), diarrhea (21%), nausea (17%), and vomiting (12%). Most toxicities were grade 1 or 2, however, there were two cases of grade 3 pain (severe pain limiting self care and activities of daily living) and one case of grade 3 ascites (severe symptoms, invasive intervention indicated). One patient developed acute renal failure following SIRT. There were no treatment-related mortalities (within 30 days of SIRT). Conclusions: Resin based SIRT is a safe and well-tolerated therapy option for patients with BCLC stage C HCC. Treatment is well tolerated even in patients with portal vein thrombus. Poster 69: Impact of Histologic Tumor Grade on Radiologic Response and Clinical Outcomes after Conventional Transarterial Chemoembolization of Hepatocellular Carcinoma J. Owen, R. Lokken, J.T. Bui, A.J. Lipnik, C.E. Ray Jr., R.C. Gaba. Radiology, University of Illinois Hospital & Health Sciences System, Chicago, IL. Objective: While transarterial chemoembolization (TACE) is a fundamental pillar of hepatocellular carcinoma (HCC) therapeutic management, treatment protocols for this procedure are relatively uniform despite potential differences in tumor characteristics—such as imaging phenotypic morphology and histopathological grade—that may conceivably result in varying imaging response and clinical outcomes. This study was undertaken to investigate the influence of histologic tumor grade on the radiologic and clinical response outcomes of conventional (c-TACE) treatment for HCC. Methods: Patients included in this single-institution retrospective study were culled from a registry of 188 patients who underwent c-TACE for HCC from 2007-2013. Patients with core needle biopsy-proven HCC index tumors were selected for analysis. Edmondson-Steiner (ES) histologic tumor grades (1-4) were assigned by a board-certified pathologist with clinical expertise in liver pathology. c-TACE was performed with Lipiodol and doxorubicin/cisplatin/mitomycin-C emulsion. Patient record and imaging review was utilized to obtain demographic and disease history, tumor response data, and local time-to-progression (TTP) and transplant-free survival (TFS) outcomes, as calculated from time of first c-TACE treatment. Outcomes were stratified and compared across histologic tumor grades pooled in a binary fashion, with ES grades 1/2 compared to 3/4. Results: The final 48 patient study cohort included 34 men and 14 women (mean age 57 years, BCLC 0=4%, A=31%, B=44%, C=15%, D=6%) with 48 index tumors (mean size 4.7 cm, 13% with portal vein invasion) treated with mean 1.7 c-TACE sessions (85% segmental, 15% lobar). Biopsy grades included 1 (n=13), 2 (n=18), 3 (n=9), and 4 (n=3). Adjunctive ablation was performed in 31% (no differences in ablation rates between histology grade groups, p>0.05). Objective response (complete plus partial response) rates were not statistically different between groups (EASL: 68% grade 1/2 versus 64% grade 3/4, p>0.999; mRECIST: 55% grade1/2 versus 36% grade 3/4, p=0.484). Median local TTP was longer for grade 1/2 tumors versus grade 3/4 tumors (279 versus 183 days), but this difference was not statistically significant (p=0.822). TFS favored grade 1/2 tumors versus grade 3/4 tumors (20.3 versus 11.1 months), but this difference was not statistically significant (p=0.747). Conclusions: Imaging and clinical outcomes of c-TACE for HCC appear to be similar in this small study. Nonetheless, further larger scale investigation of the influence of tumor histopathology on TACE therapeutic efficacy is relevant given the potential importance of tumor biological features.

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Poster 70: Imaging and Clinical Outcomes of Conventional Transarterial Chemoembolization for Hypovascular Hepatocellular Carcinoma J. Owen2, J.T. Bui5, R. Lokken4, A.J. Lipnik6, C.E. Ray Jr.3, R.C. Gaba1. 1 Radiology, University of Illinois Hospital & Health Sciences System, Chicago, IL; 2Radiology, University of Illinois, Chicago, IL; 3Radiology, University of Illinois, Chicago, IL; 4Radiology, University of Illinois, Chicago, IL; 5Radiology, University of Illinois, Chicago, IL; 6Radiology, University of Illinois, Chicago, IL.

Poster 71: CT and MRI Imaging Findings of Hepatocellular Carcinoma in Patients with Underlying Hepatitis B vs. Hepatitis C Virus Infection N. Limninart, N. Tanpowpong, N. Pinjaroen. Radiology, Chulalongkorn university, Bangkok, Thailand. Objective: Hepatocellular carcinoma(HCC) is the one of the leading cause of cancer related death in Thailand which its prevalence largely attributed to viral hepatitis including hepatitis B virus (HBV) and hepatitis C virus (HCV). HBV and HCV have different oncogenic mechanisms which may impact tumor presentation and radiologic findings. This study aims to compare the imaging findings of contrast-enhanced CT and MRI at diagnosis of HCC between patients with HBV infection and HCV infection. Methods: We retrospectively reviewed multiphase contrast-enhanced CT and MRI of patients diagnosed with HCC (based on AASLD guideline 2011) from November 2012 to June 30 2015. A total of 210 patients were included which consists of 145 patients in HBV group and 65 patients in HCV group. Radiologic findings of each groups wrere compared and analysed. Results: There was significant larger number of patients who underwent MRI in HCV group ((HBV, 55/145; 38% vs HCV 35/65; 54%) (p = 0.031). Base on imagings, prevalences of liver cirrhosis between HBV group (129/145; 89%) and HCV group (62/65; 95%) are not significant differrent (p = 0.134). HCV group was more likely to had radiologic signs of portal hypertension (56.6% vs 73.8%; p = 0.017). In HBV group, patients had larger maximal tumor diameter than HCV group (7.8r6.3 cm vs 4.8r3.9 cm; p <0.001). Most tumors had typical enhancement pattern. There were only 4 patients with atypical enhancement (HBV, 2/145; 1.4 % vs HCV 2/65; 3.1 %) (p = 0.589). HBV group was more commonly found to be in bilobar in distribution (35% vs 22%; p = 0.048), associated with portal vein invasion (39.3% vs 23.1%; p = 0.022) and hepatic vein invasion (20.7% vs 7.7%; p = 0.035) than HCV group. There were no statistically significant differences in morphological pattern, fat metamorphosis, tumor rupture, biliary system involvement, adjacent organ invasion, and distant metastasis between HBV and HCV groups.

Conclusions: HBV-associated HCCs have unfavorable tumor characteristics in terms of larger tumor size, more common in bilobar distribution, more associated with portal vein invasion and hepatic vein invasion than HCV-associated HCCs. Although, HCCs in both HBV and HCV groups are commonly found in background of liver cirrhosis. HCV group is more frequently associated with radiologic findings of portal hypertension which may imply poorer liver functional status than HBV group. Imaging findings of HCC in patient with underlying HBV versus HCV infection

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Objective: Transarterial chemoembolization (TACE) exploits the preferential hepatic arterial supply of hypervascular hepatocellular carcinoma (HCC) to deliver high dose, targeted cytotoxic chemotherapy to induce tumor necrosis. Given that TACE locoregional therapy is contingent on tumor arterial supply, it remains unclear whether carcinomas lacking robust arterial flow respond to TACE with similar efficacy as compared to arterially enhancing lesions. This study was thus undertaken to investigate the radiologic and clinical response outcomes of conventional (c-TACE) treatment for hypovascular HCC. Methods: Patients included in this single-institution retrospective study were culled from a registry of 188 patients who underwent c-TACE for HCC from 2007-2013. Patients with hypovascular HCC index tumors, defined as those tumors lacking classic arterial enhancement on diagnostic cross-sectional computed tomography or magnetic resonance imaging as defined by NCCN guidelines, were selected. c-TACE was performed with Lipiodol and doxorubicin/cisplatin/mitomycin-C emulsion. Patient record and imaging review was utilized to obtain demographic and disease history, tumor response data, and time-to-progression (TTP), progression-free survival (PFS), and transplant-free survival (TFS) outcomes, as calculated from time of first c-TACE treatment. Results: The final 22 patient study cohort included 15 men and 7 women (mean age 60 years, BCLC 0=5%, A= 50%, B=27%, C=9%, D=9%) with 22 hypovascular index tumors (mean size 4.2 cm, 9% with portal vein invasion, all showing classic portal venous phase washout) treated with mean 1.4 c-TACE sessions (91% segmental, 9% lobar). Adjunctive thermal ablation was performed in 18%. Objective response (complete plus partial response) rates included size response in 27% (WHO) and 23% (RECIST), and necrosis response in 59% (EASL) and 59% (mRECIST). Median local TTP, distant site TTP, local PFS, and other site PFS were not reached, not reached, 9.9, and 10.5 months. 14% underwent liver transplantation. TFS for the entire cohort was 12.7 months (22.2, not reached, and 3.5 months for BCLC 0/A versus B versus C/D, respectively). Conclusions: c-TACE results in acceptable imaging and clinical response outcomes in hypovascular HCC, although TFS may be slightly dampened when compared to published data from other c-TACE series. The current results indicate need for further study of locoregional therapy efficacy in this specific patient population.

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Poster 72: Need to Establish a Convention for Conventional TACE M.U. Shahid, N. Sabbah, S. Contractor. Radiology, Rutgers New Jersey Medical School, Newark, NJ. Objective: Review existing literature on therapy regimen and global practice patterns for TACE and attempt to define a standardized chemoembolic regimen. Methods: Trans-arterial chemoembolization (TACE) is commonly performed to treat BCLC Stage B hepatocellular carcinoma (HCC). TACE for liver cancer has been proven to be useful in local tumor control and prolong survival. A variety of chemotherapeutic agents (mitomycin, cisplatin, doxorubicin) and embolic agents (lipiodol, gelfoam, embolic particles)have been used. However, no consensus exists on the best embolic regimen. Herein we review the chemotherapeutic regimens as reported and present efficacy and side effect profiles. Review was performed by searching Medline and Google for published metaanalysis and review articles as well as original articles reporting technique, efficacy and side effect profiles. English language studies and reports that had at least 15 patients reported were included. Data extracted included number of patients, embolic protocol, efficacy and side effect profile. Results: Tables preapred exceed character limit and could not be included. Can be emailed separely as requested.24 studies were included in this review covering a total of 1147 patients. 8 Different embolic protocols were identified, based on choice of chemo agent utilized, dosage of the specific agents or combinations with which different drugs were mixed. 9 other protocols were found as well that varied based on standard dosing of chemo agents. Doxorubicin, Cisplatin and Epirubicin were identified as most common chemo agents and gelatin sponge particles as the most common embolic agent used. The most efficacious protocol based on Overall Survival was mixture of iodized oil and doxorubicin hydrochloride followed by embolization with grated gelatin sponge particles which yielded a 2 year OS of 83.6% [14]. The amount of of administered oil (10-25 ml mean 16.6ml) and doxorubicin HCL (50-75 mg, mean 57.0 mg) was empirically chosen based on number and diameter of lesions. The safest protocols were a mixture of 50 mg Doxorubicin with lipiodol and an Emulsion 5-20 ml iodized oil with 40-80 mg doxorubicin, both of which had no grade ¾ adverse drug effects [7,9]. The protocol with the most unfavorable safety profile included 50mg cisplatin, followed by TAE performed 4-6 hours after cisplatin administration with an 83.7% grade 3/4 ADE [Meyer, 1], and lipiodol combined with doxorubicin [Maleux,1], which had an 53% Grade 3 ADE. Despite several societal guidelines published on TACE (CIRSE, SIR), a chemo embolic protocol is still not defined and much variation in practice exists. Conclusions: This review demonstrates that conventional chemo standardization as practised is widely variable, raising concerns of ineffective procedures as well as likelihood of embolizations with higher adverse events being performed. The most suitable regimen appears to be a mixture of iodized oil and doxorubicin HCL and

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should likely be the one studied in a randomised manner to further define its advantageous. Poster 73: Comparative and Cost-Effectiveness of Cancer Directed Therapy for Unresectable Hepatocellular Carcinoma: A SEER-Medicare Population Study

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M. Xing1, N. Kokabi2, H.S. Kim1. 1Interventional Radiology, Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT; 2Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA. Objective: To investigate comparative and cost-effectiveness of cancer-directed therapies and their impact on survival in unresectable hepatocellular carcinoma (HCC) using the Surveillance, Epidemiology and End Results Medicare-linked database (SEER-Medicare). Methods: Using the most updated SEER-Medicare linked database, unresectable HCC patients 65 years and over diagnosed between 2000 and 2012 and followed to 2014 were identified and stratified by American Joint Commission on Cancer (AJCC) staging and the following therapies: ablation (including radiofrequency, microwave and cryoablation), trans-arterial chemoembolization (TACE), Yttrium-90 radioembolization (Y90), and surgical palliation (surgery with curative intent and transplant excluded). Overall survival (OS) of patients receiving cancer-directed therapies was estimated using Kaplan-Meier method and log-rank test. Total reimbursements and incremental cost-effectiveness ratio (ICER) between therapies compared to no cancer-directed therapy were evaluated. Results: A total 16,551 unresectable HCC patients were included, of which 1,128 (6.9%) received ablation, 5,268 (31.8%) received TACE, 1,089 (6.6%) received Y90, and 293 (1.8%) received surgical palliation. All therapies demonstrated OS benefit compared to no cancer-directed therapy, with overall median survival of 30.8 months for ablation, 15.6 months with Y90, 15.5 months with TACE and 6.8 months with surgical palliation (p-values<0.001). For AJCC Stage I patients, ablation was the most cost-effective therapy with an ICER of $9,469.85 (inter-quartile range, IQR 2,482.37-11773.61), compared to no cancer-directed therapy. For AJCC Stage II and III patients, TACE and Y90 were most cost-effective, with ICERs of $11,652.25 (IQR 6,829.35-12,448.92) and $11642.77 (IQR 7,553.98-13,194.72), respectively. Conclusions: In a large-scale population study of therapies for patients with unresectable HCC, ablation was found to be the most cost-effective therapy for AJCC Stage I patients, while TACE and Y90 were the most cost-effective for AJCC Stage II/III patients.

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well-vascularized, uninodular hepatocellular carcinoma having received glass or resin microsphere Y90 radiation segmentectomy with at least 2 years imaging followup or explant pathology. Administered dose, serum alpha feto-protein levels and adverse clinical and laboratory events were assessed. Segmental doses were calculated using a uniform distribution assumtion the formula D = (50)(infused activity)(1 – lung shunt fraction)/(mass of infused liver). Tumor doses were calculated assuming a standard hypervascularity of 0.3 and substituting the segmental mass with the mass of the tumor. A ratio of 0.6 was used for the largest, most vascular tumor. Two experienced abdominal radiologists determined tumor response with either dynamic contrast enhanced CT or MRI using mRECIST criteria, with discrepancies adjudicated by a third experienced abdominal radiologist. Results: Five patients were identified who met criteria. Baseline patient, tumor and dose characteristics are described in Table 1. Four patients received resin microspheres, and 1 patient received glass. Explant pathology was obtained for two patients who underwent liver transplantation at 7 and 12 months after segmentectomy. Pathology in both transplanted patients revealed 100% tumor necrosis and no viable tumor within the treated segments. Complete response by mRECIST criteria was attained in all patients throughout follow-up. Follow up for the 3 patients who did not receive transplants was 25, 26 and 37 months. Four of 5 patients had normal baseline AFPs (<15 ng/ml). One patient had a baseline AFP of 31.1 ng/ml which normalized to 12.3 ng/ml on post-treatment follow-up. AFP remained normal in all patients throughout the follow-up period. No major (SIR class C or CTCAE v4.0 grade 3 or greater) clinical or laboratory toxicities were identified. Conclusions: Highly selected patients with homogeneously well-arterialized uninodular HCC who are not candidates for resection or ablation may benefit from radiation segmentectomy with curative intent. Larger, prospective and, ideally, randomized studies are required. Baseline patient, tumor and dose characteristics

For patients treated via two different segments, data are total including both segments. Poster 75: US Findings After Irreversible Electroporation Ablation: Can the Size of the Ablation Zone be Predicted Earlier? M. Lin, X. Xie. Department of Medical Ultrasound, Institute of Diagnostic and Interventional Ultrasound, Guangzhou, China.

Poster 74: A Short Case Series: Is Radiation Segmentectomy with Curative Intent Feasible? A.S. Kierans, J.O. Chen, D.O. Brylka, M.D. LaGratta, A.D. Talenfeld. Radiology, Weill Cornell Medical College, New York, NY. Objective: Radiation segmentectomy has been reported as a safe and effective, but not as of yet curative. We present a series of 5 patients experiencing a durable complete response to resin or glass microsphere radiation segmentectomy for uninodular HCC. Methods: With IRB exemption, a retrospective chart review was performed of our institution’s Y90 quality-improvement database beginning 1/2011. Unresectable patients were selected who were treatment naïve, with homogeneously

Objective: To describe the performance of baseline ultrasound (BUS) and contrast-enhanced ultrasound (CEUS) within 2 hours after irreversible electroporation (IRE) ablation and to determine if the size of the ablation zone can be predicted early after IRE ablation. Methods: The institutional animal care and use committee approved the use of the animal model in this study. Six IRE ablations were performed in the livers of two miniature pigs in vivo under ultrasound (US) guidance. BUS and CEUS assessments were performed at four time intervals within 2 hours (phaseA, B, C and D) after IRE ablation. The boundary of the ablation zone on US was defined by the consensus of two radiologists, and the length and width of the ablation zone were measured. Animals were sacrificed 2-3 hours after the last IRE ablation. The size of the ablation zone was assessed by gross pathology and was defined as the reference standard. The sizes measured by US assessment at different time intervals were compared to the gross pathological assessment by paired two-tailed Student tests, and the deviations between them were calculated. Results: The BUS and CEUS images of the IRE ablation zone evolved overtime and differed from each other at different time intervals after IRE ablation. Gross pathological assessment indicated that the ablation zone was 3.4r0.2 cm in length (range: 3.1-3.7 cm) and 2.3r0.2 cm (range: 2.0-2.6 cm) in width. The greatest accuracy was observed in the portal phase at CEUS assessment at phase A when the ablation zone was defined as non-enhanced area, with deviations of 0.05r0.08 cm in length (p=0.202) and -0.05r0.08 cm in width (p=0.203). The measurement obtained by BUS

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assessment at phase C also exhibited great accuracy, with deviations of 0.07r0.12 cm in length (p=0.235) and -0.03r0.05 cm in width (p=0.175). The sizes of the ablation zone measured by BUS assessment at phase A and B and by CEUS assessment at phase B, C and D were all significantly smaller than the reference standard (all p<0.05). Conclusions: BUS and CEUS images within 2 h after IRE ablation are dynamic and evolving. The non-enhancement area in the portal phase upon CEUS assessment within 10 min after IRE ablation best predicts the size of the IRE ablation zone. CEUS assessment can allow the size of the ablation zone to be predicted earlier after IRE. Poster 76: Cost Analysis of Surveillance Imaging Protocols in Renal Mass Ablation Patients S.E. Dreyer, K. Ahrar, S. Kusin, S.H. Sabir. Interventional Radiology, MD Anderson Cancer Center, Houston, TX.

Poster 77: Cutaneous Manifestations Following Nontarget Drug-Eluting Beads Transarterial Chemoembolization (DEB-TACE) of Liver Tumors: Clinical Course and Management C. Patel, M. Zanini, B. Achakzai, S. Schwartz. Interventional Radiology, Henry Ford Hospital, Utica, MI. Objective: 1. Describe anatomy and variants of the falciform ligament and right internal mammary arteries, and importance related to liver embolization procedures. 2. Discuss techniques to minimize non-target embolization and illustrate the clinical course and management of associated skin injury with photographs demonstrating its natural progression. Methods: Major complications of drug-eluting beads transarterial chemoembolization (DEB-TACE) of liver tumors include nontarget chemoembolization, liver failure and hepatic abscess. The cutaneous complications of nontarget embolization may manifest as itching, erythema with skin and/or fat necrosis. We will illustrate the clinical course of the cutaneous manifestations of nontarget chemoembolization involving the falciform ligament and right internal mammary arteries through clinic photographs and discuss our experience in management. Results: Patient 1 is a 69 year old male with multifocal hepatocellular carcinoma status post chemoembolization of left hepatic lobe tumors via selective catheterization of the right internal mammary artery. One week later, the patient presented with a painful, patchy, erythematous skin rash with several foci of purple discoloration, which was managed conservatively with Neosporin ointment. On one month follow

up, patient had well healed skin ulcerations. Patient 2 is a 66 year old male with multifocal HCC secondary to chronic hepatitis C and cirrhosis. Patient underwent multiple chemoembolization for his liver tumors. During his last chemoembolization, the falciform ligament artery was seen to arise from the segment 4 artery, which was embolized with coils after placement of ice packs over the umbilicus to constrict the falciform ligament. Despite all precautions, the patient developed skin erythema with firmness and tenderness in the paraumbilical region in two days. These skin lesions continued to grow larger and firmer with development of skin ulceration and necrosis in two weeks. Patient was directed to apply silver sulfadiazine cream twice a day with eventual improvement of skin lesions, avoiding the need for a skin graft. Conclusions: Nontarget embolization during DEB-TACE is a rare but serious complication. Conservative management with close clinical follow-up is indicated in cases with inadvertent nontarget embolization.

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Objective: Various protocols regarding the frequency of surveillance imaging of patients who have undergone radiofrequency (RF) ablation for renal masses have been suggested1. At our institution we currently follow patients at 1, 6, and 12 months and then every 6-12 months after primary ablation to detect residual or recurrent tumors. In this analysis we evaluate the effects and follow-up CT imaging costs associated with surveillance imaging at 1, 6, and 12 months versus 6 and 12 months. Methods: All cases of percutaneous CT-guided RF ablation for renal masses performed at our institution from 2001 to 2015 were retrospectively reviewed. An imaging costs analysis model was formulated to compare two different surveillance strategies, imaging at 1, 6, and 12 months versus 6 and 12 months. The costs for surveillance scans were determined using the professional and technical fee components from the 2015 Medicare Physician Fee Schedule for CT imaging. The cost analysis model was constructed based on time to detection of recurrent disease in our patient population. Results: 258 patients underwent CT-guided RF ablation between 9/2001 and 6/2015 which had follow-up imaging for a median of 28 months (range 1-54). The mean age was 64 years (range 18-87). The mean tumor size was 2.5 cm (range 0.9-6.0). Overall, imaging evidence of residual or recurrent tumor was present in 7 (2.7%) patients with a median detection time of 5.6 months (range 0.5-24). Using the Medicare payment of $402 (including technical and professional components) for a CT of the abdomen and pelvis without and with contrast our cost analysis model demonstrates scanning at 1, 6, and 12 months post primary ablation costs $86,405 to detect 1 case of residual or recurrent disease versus $40,734 for scanning at 6 and 12 months. By eliminating the scan at 1 month post ablation from our current protocol the detection of residual or recurrent tumor would be delayed in 1/7 (14%) of patients. The patient with residual disease at 1 month leading to repeat intervention had Von Hippel-Lindau syndrome with multiple bilateral masses and early detection of residual disease likely would not change clinical outcome as she was on an active surveillance protocol. One patient with imaging evidence of recurrent disease at 24 months underwent CT guided biopsy however pathology findings were negative for tumor. Conclusions: Cost analysis of CT follow-up at our institution suggests that imaging at 6 and 12 versus 1, 6, and 12 months post primary radiofrequency ablation for renal masses would result in significant imaging cost reduction while delaying detection and treatment of recurrent tumor in a small fraction of patients.1. Matin, S. F. et al. Residual and Recurrent Disease Following Renal Energy Ablative Therapy: A Multi-Institutional Study. J. Urol. 176, 1973–1977 (2006).

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Cutaneous manifestation 2 weeks status post DEB-TACE. Poster 78: Do Clinical Variables Augment Multi-Parametric MRI Computer-Aided Diagnosis? J. Kwak, S. Xu, B. Turkbey, P. Choyke, P. Pinto, B.J. Wood. National Institutes of Health, Bethesda, MD. Objective: To investigate the additive value of clinical variables to a computer aided-diagnosis (CAD) system for detection of prostate cancer using multi-parametric magnetic resonance imaging (MRI). Methods: Previously, a CAD system for detecting prostate cancer that utilizes texture information from two MRI sequences (T2-weighted MRI and high-b-value diffusion-weighted imaging (DWI)) wan developed. 124 texture features based on local binary pattern (LBP) and its variants were extracted and used to characterize cancers on MRI. Adding two clinical variables (age and prostate-specific antigen (PSA) level) to the existing 124 texture features, the CAD system was re-trained and validated. The training dataset included 108 patients with 78 MR-positive prostate cancers and 105 benign MR-positive lesions (mean age of 63.2 years ranging 36-79 years; mean PSA level of 11.6 ng/mL ranging 1.4-62.1ng/mL) and the validation dataset contained 118 patients with 68 MR-positive prostate cancers and 111 MR-positive benign lesions (mean age of 64.0 years ranging 42-85 years; mean PSA level of 10.7 ng/mL ranging 0.7-75.7ng/mL). Results: Combining clinical variables and texture features, the CAD system achieved an area under receiver operating characteristics curve (AUC) of 0.84 (95% confidence interval (CI): 0.77-0.90) in distinguishing MR-positive prostate cancers from MR-positive benign lesions. The result was superior to that of the CAD system without clinical variables (0.83 AUC (95% CI: 0.76-0.89)). The difference between the two AUCs was statistically significant (p-value<0.05) when bootstrap resampling with 200 repetitions was used. Conclusions: Clinical variables were able to improve the performance of a multi-parametric MRI CAD system for identifying prostate cancer. This indicates that clinical variables may complement texture imaging features, or vice versa.

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Poster 79: Incidentally-Found Miliary Liver Lesions on Cone-beam CT Angiography: Higher Risk for Metastatic Hepatic Disease Progression

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B.C. Odisio1, V.L. Cox2, A. Mahvash1, A.L. Tam1, R. Murthy1, X. Shi3, S. Gupta1, S.C. Faria2, M.J. Wallace1. 1Interventional Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX; 2 Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX; 3Diagnostic Radiology, Baylor College of Medicine, Houston, TX. Objective: To determine if incidentally-found miliary liver lesions (IML) on conebeam CT angiography (CBCTA) portend a worse prognosis in patients with metastatic hepatic tumors treated by transarterial embolotherapy. Methods: This is a single-Institution IRB-approved 5-year retrospective analysis. Inclusion criteria comprised patients with estimated metastatic tumor burden d 25% of the liver volume, who had CBCTA during transarterial embolotherapy, and pre-procedure imaging (computed tomography or magnetic resonance) within 45 days prior to the transarterial procedure. 52 patients with various metastatic tumors were included. Average number of CBCTA per patient was 1.4 (range, 1-4). IML were defined as the presence of multiple subcentimeter hyperattenuating lesions on CBCTA that were not appreciable on pre-procedure cross-sectional imaging (figure 1). Progression-free survival to the liver (PFS-L), target lesion(s) (PFS-TL), and extra-hepatic disease (PFS-EHD) were performed by two radiologists blinded to CBCTA results. Recorded variables were compared between patients with versus without IML utilizing a t-student test and a log-rank test. Results: Sixteen (30%) patients had IML, all identified on the CBCTA during the first transarterial therapy session. Patients with IML were comparable to patients without IML as demonstrated by the non-significant differences in regards days from pre-procedure imaging to procedure (17.8 versus 23.6 days), pre-procedure magnetic resonance use (37.5% versus 25%), post-procedure imaging follow-up (18 versus 21.5 months), mean largest target tumor diameter (3.5 versus 3.8 cm), and number of liver lesions on pre-procedure imaging (multiple in 50% and 61%), respectively. PFS-L was significantly shorter on patients with IML compared to patients without IML (3.8 versus 9.6 months, respectively; p= 0.035). PFS-TL (5.4 versus 8.4 months, p=0.66), PFS-EH (5.9 versus 9.2 months, p=0.13) were not significantly different between the two groups. Conclusions: IML on CBCTA are a relatively common finding in patients with metastatic hepatic tumors submitted to transarterial embolotherapy and are associated with a significantly shorter hepatic progression-free survival. Further work is needed to determine the accuracy of such finding and the potential role for its application in treatment decision-making strategies.

Incidentally-found miliary lesions during CBCTA: arterial (A) and venous (B) CT images of the hepatic dome 15 days before transarterial embolization procedure on a patient with a single leiomyosarcoma metastasis to the liver (not shown). Axial (C) and coronal (D) reconstructed MIP CBCTA images obtained for identification of vessel supply to the single metastatic lesion (*) showing multiple subcentimeter hyperattenuating lesions on the hepatic dome not previously identified on CT.

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Poster 80: Quantitative Therapy Planning and Assessment of Lipiodol Deposition After Conventional Transarterial Chemoembolization (cTACE) by Volumetric Inter-Modality Comparison and Analysis of Spatial Overlap of HCC Lesions on MRI and CT S. Smolka1, J. Treilhard5, S. Hussain3, S. Rashid2, W. Manzano4, J. Chapiro6, B. Gebauer7, J. Geschwind8, J. Duncan9, M. Lin10. 1Charite University Hospital Berlin, Berlin, Germany; 2Diagnostic Radiology, Yale New Haven Hospital, Hamden, CT; 3Radiology, Yale New Haven Hospital, New Haven, CT; 4School of Medicine, University of California, Irvine, Irvine, CA; 5Yale School of Engineering and Applied Sciences, New Haven, CT; 6Charite University Hospital, Berlin, Germany; 7Charite University Hospital, Berlin, Germany; 8Yale School of Medicine, New Haven, CT; 9Yale School of Engineering and Applied Sciences, New Haven, CT; 10Philips Research North America, Cambridge, MA. Objective: Quantitative analysis is gaining importance in radiology, imaging related to TACE is following this trend (e.g. quantitative EASL [qEASL]). For the next step, the different modalities involved in treatment planning (MR) and assessment (CT) after conventional TACE (cTACE) require the quantitative analysis to advance to a multimodal approach as well. In order to enable this process, our study investigates the spatial and volumetric overlap of targeted HCC lesions on baseline MR and follow-up CT in patients with hepatocellular carcinoma (HCC) treated with conventional TACE (cTACE). Methods: In our single center retrospective study includes 20 consecutive patients (27 HCC lesions total) receiving cTACE between June 2014 and June 2015. Patients had baseline multi-phasic MR 4 weeks prior to TACE and CT 24 hours afterwards. MR and CT images were registered with the transformation generated by a robust point matching algorithm (BioImage Suite, Yale School of Medicine) aligning the liver surfaces of both images. Tumors were segmented semi-automatically using GeoBlend (Medisys, Philips Research, Suresnes, France). The spatial overlap between corresponding tumors on the MR and CT images was measured by calculating the Dice Similarity Coefficient (DSC) of the two tumor segmentations. The DSC varies between 0 (no spatial overlap) and 1 (complete overlap). DSC values greater than 0.75 represent are considered excellent agreement, between 0.75 and 0.40 a good agreement, and below 0.4 a poor agreement. Results: There was good spatial agreement between the lesions segmented on MR and CT - median DSC = 0.69+-0.22. Median MR tumor volume was 16.8+-454.4 cm3 (3.4 to 2007.3 cm3); median CT tumor volume was 14.4+-566.7 cm3 (3.2 to 2583.1 cm3). The DSC computed for a single lesion was highly correlated with the tumor volume (P-value = 0.002). This strong correlation as well as the similar volumes indicate that imperfect volumetric overlap between lesions segmented on MR and CT images is partially due to imperfect registration rather than inter-modality disagreement or tumor growth. This was confirmed by visual evaluation. Conclusions: Robust quantitative inter-modality comparison of segmented HCC lesions on baseline MR and follow-up CT is feasible, as shown by high inter-modality DSC. This enables quantitative inter-modality planning and assessment of Lipiodol deposition in cTACE.

Upper row: Arterial phase MRI with the tumor segmentation based on the baseline MR (yellow) and the tumor segmentation based on the follow-up CT (red). Lower row left : 3 D visualization of the tumor segmentations of the case from above showing a Dice Similarity Coefficient (DSC) of 0.72. Lower row right: Diagram showing an increase of DSC with tumor size, indicating registration as a source of error.

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Poster 81: Investigation of Spatial Overlap of Whole Liver Segmentation on Baseline MR and Follow-up CT for Quantitative Inter-Modality Planning and Assessment of Lipiodol Deposition in Conventional Transarterial Chemoembolization (cTACE) S. Smolka1, J. Treilhard4, W. Manzano3, J. Chapiro5, R. Ardon2, B. Gebauer6, J. Geschwind7, J. Duncan8, M. Lin9. 1Charite University Hospital Berlin, Berlin, Germany; 2Medisys, Philips Research, Suresnes, France; 3School of Medicine, University of California, Irvine, Irvine, CA; 4Yale School of Engineering and Applied Sciences, New Haven, CT; 5Charite University Hospital, Berlin, Germany; 6Charite University Hospital, Berlin, Germany; 7Yale School of Medicine, New Haven, CT; 8Yale School of Engineering and Applied Sciences, New Haven, CT; 9Philips Research North America, Cambridge, MA.

Baseline MR and follow-up CT and 3 D visualization of their corresponding liver segmentations. On the right the MR in greyscale is overlaid with the registered CT in red. The green outline represents the liver segmentation based on the MR, the yellow outline represents the one based on the CT. The Dice Similarity Coefficient (DSC) of the liver segmentations is 0.85 Poster 82: Chemical Shift MRI of Lipiodol Delivery after cTACE – Multi-Center Experience in HCC Patients A.C. Gordon1, R.J. Lewandowski1, W. Li1, S. Brinckerhoff1, S. Giri1, X. Zhong4, S.A. Kannengiesser3, E.A. Gonda1, F.H. Miller1, R. Salem1, W. Rilling2, A.C. Larson1, S.B. White2. 1Radiology, Northwestern University Feinberg School of Medicine, Chicago, IL; 2Vascular & Interventional Radiology, Medical College of Wisconsin, Milwaukee, WI; 3 Siemens Healthcare GmbH, Erlangen, Germany; 4Siemens Healthcare, Atlanta, GA. Objective: Functional monitoring after conventional transarterial chemoembolization (cTACE) should include quantitative measurements of lipiodol retention in

targeted tumor tissues so that future interventions (i.e. retreatment and choice of loco-regional or systemic therapy) may be guided based on lesion-specific information. The objective of this study was to demonstrate feasibility of using chemical shift fat/water quantification magnetic resonance imaging (CS-MRI) methods to visualize and quantify lipiodol content in hepatocellular carcinoma (HCC) treated with chemoembolization. We hypothesized these metrics are linked to tumor response on follow-up MRI. Methods: Fifteen HCC patients (eleven male; mean age 67 years; 60% solitary disease; 1 branch portal vein tumor thrombus) treated with cTACE at two centers were evaluated with follow-up CS-MRI at 1.5 or 3T (MAGNETOM Aera and Verio, Siemens Healthcare) using a prototype sequence. The infused doxorubicin dose was recorded in each patient. Tumor lipiodol uptake was evaluated based on procedural cone-beam CT or non-contrast CT within 24 hours of the procedure, and follow-up CS-MRI. Each patient also received follow-up contrast-enhanced imaging assessment for response by modified Response Evaluation Criteria In Solid Tumors (mRECIST). Dosimetry metrics included tumor lipiodol volume (CT and CS-MRI), attenuation (CT), tumor fat percentage (CS-MRI), enhancement (CT), and tumor:normal ratio (CS-MRI) were compared for responders vs. non-responders. Results: CS-MRI enabled visualization of tumor size and evaluation of lipiodol content in 22 lesions after 17 treatment cycles. Lipiodol retention within tumors was common with focal fat signal in 41% (9/22) at a median of 32 days post-chemoembolization. The response rate by lesion was 41% (9/22). The average doxorubicin dose per lesion was 29.4 mg/lesion versus 14.7 mg/lesion in responders vs. non-responders, respectively (p=0.047). Tumor volume as measured on same-day non-contrast CT and tumor lipiodol volume on follow-up CS-MRI were correlated on linear regression (R2=0.948), but neither metric was significantly different for responders and non-responders. The average fat percentage was 5.8% in responders vs. 6.4% in non-responders (p=0.680). Focal fat signal was present in 22% (2/9) of responders and 54% (7/13) of non-responders (p=0.203) while <20 mg doxorubicin + focal fat signal was present in 0% (0/9) of responders and 38% (5/13) non-responders (p=0.054). Conclusions: CS-MRI allows functional assessment of lesion-specific lipiodol delivery following chemoembolization. Lipiodol retention in treated lesions after cTACE is relatively common at 1-month and can be visualized on CS-MRI. The clinical significance of this remains undefined; however, lipiodol retention was rarely observed in responders based on mRECIST.

Images from a 60-year-old male with HCC in segment V. Post-cTACE CT confirmed lipiodol delivery to this hypervascular HCC (top left). Baseline contrast-enhanced (CE) MRI shows enhancing region measuring 1.8x1.4cm (bottom left). Follow-up MRI 1mo later shows nodular enhancement measuring 1.7x1.0cm (bottom right) that correlated with lipiodol retention on CS-MRI (top right). Poster 83: Percutaneous Ablation of Metastatic Soft Tissue Sarcomas: An Oncological Outcome A.M. Ayalew, J.M. Morris, A.N. Kurup, A.J. Weisbrod, T.D. Atwell, G.D. Schmit, J.J. Schmitz, M. Callstrom. Radiology, Mayo Clinic, Rochester, MN Objective: To determine the early oncological outcomes and safety of percutaneous thermal ablation in the management of metastatic soft tissue sarcomas.

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Objective: Inter-modality image analysis has become an important component of therapy planning and follow up after conventional TACE (cTACE). As the field evolves from qualitative to quantitative analysis, there is a need for inter-modality comparison to be validated volumetrically. Our study investigates a fundamental component required for lesion and enhancement pattern analysis, the spatial and 3 D volumetric overlap (quantified by Dice Similarity Coefficient – DSC) between whole liver segmentations on MR and CT of patients with HCC treated with cTACE. Methods: Our retrospective single center study includes consecutive 20 patients with HCC who received cTACE in 2014 and 2015. Patients had MR imaging within 4 weeks prior to TACE and CT 24 hours afterwards. The corresponding MR and CT images were registered via an affine, intensity-based registration (BioImage Suite, Yale School of Medicine, New Haven, CT). The whole liver was segmented on MR and CT images using a prototype software (LiverMR, Medisys, Philips Research, Suresnes, France). Liver volumes at each imaging session were noted and the volumetric spatial overlap was measured by calculating the Dice Similarity Coefficient (DSC) between the two whole liver segmentations for each patient. The DSC varies between 0 and 1, where 0 implies no spatial overlap and 1 represents identical regions with perfect overlap. DSC values greater than 0.75 represent an excellent agreement, between 0.75 and 0.40 a good agreement, and below 0.4 a poor agreement. Results: The median DSC of the whole liver segmentations was 0.85+-0.09 (measured median MR liver volume = 1936+-788 cm3, CT liver volume = 2032+-770 cm3). The DSC was highly correlated with the volume of the liver under consideration (P=0.038) - linearly regressing the DSC on the logarithm of the liver volume yielded slope = 5.13 e-05+-2.29e-05. This strong correlation indicates that imperfect volumetric overlap between whole livers segmented on MR and CT images respectively is partially due to registration error, which was also apparent by visual evaluation. Conclusions: Robust quantitative inter-modality comparison of the liver between baseline MR and follow-up CT is feasible, as shown by high inter-modality DSC. This provides the foundation for multi-modality lesion and enhancement pattern analysis.

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Methods: Retrospective, single institution review revealed a total of 17 patients with metastatic soft tissue sarcomas who underwent 24 percutaneous ablation procedures between 2005 and 2010. Study end points include local tumor control, progression free survival and procedural complications. Results: Local control was achieved in 14 out of 24 tumors (58%) with a median follow up of 8 months (range of 0.7-79 months). Local recurrence was observed in 5 tumors (21%) with a median time of recurrence of 3.5 months (range of 1.9-22.8 months). Distant metastases were seen in 4 cases (17%). One patient expired before follow up. Estimated progression free survival at 5 and 10 months were 61% and 39% respectively. There were 4 CTCAE grade 3 or higher procedural complications; one patient experienced thermal injury to skin with ulceration. One patient had pain and pleural effusion which required rehospitalization. One patient developed decreased sensation over the leg and foot. Conclusions: Percutaneous thermal ablation has acceptable local control of metastatic soft tissue sarcomas. This procedure can be performed safely with a low rate of major complications. Poster 84: Safety of Lobar Hepatic Arterial Embolization In Metastatic Uveal Melanoma Patients with underlying Gilbert’s Disease D.C. Feldstein1, R. Adamo1, C. Gonsalves1, D. Eschelman1, M. Orloff2, T. Sato2. 1Interventional Radiology, Thomas Jefferson University Hospital, Jenkintown, PA; 2Medical Oncology, Thomas Jefferson University Hospital, Philadelphia, PA. Objective: Gilbert’s syndrome, also known as benign unconjugated hyperbilirubinemia, is a hereditary disorder leading to elevated levels of serum bilirubin. Elevated bilirubin levels are typically considered a relative contraindication for lobar hepatic arterial embolization treatment. This study evaluates the safety of lobar hepatic artery treatment in patients with metastatic uveal melanoma and a known diagnosis of Gilbert’s disease. Methods: A retrospective chart review was performed of all patients with Gilbert’s disease who underwent lobar hepatic artery treatment between September 2003 and February 2015. The following information was collected: patient demographics, number of treatment sessions, pre- and post- laboratory values, and patient status. A total of 6 patients underwent 48 embolization procedures over a 12 year period including chemoembolization (22 procedures), immunoembolization (25 procedures), and radioembolization (1 procedure). Results: A total of 30 procedures (63%) were performed with elevated pre-treatment total serum bilirubin levels (>1 - 2 mg/dL; range 1.1-1.8); 2 (4%) procedures with pre-treatment levels (>2 - 3 mg/dL; both 2.3), and 1 (2%) procedure with pre-treatment level (>3 mg/dL; max 3.8). Total serum bilirubin levels demonstrated a mean 48% increase, while direct bilirubin levels showed a 44% increase and unconjugated bilirubin levels a 49% increase immediately post-treatment. Sequential post-embolization laboratory values were available in the medical record for 22 procedures in 3 patients. Normalization of total serum bilirubin levels to pre-embolization baseline values occurred on average 8 days post-embolization (range 4-20 days). Of the 22 procedures with available longitudinal laboratory data, 77% (n=17) did not demonstrate a significant elevation of greater than 0.5 mg/dL. All patients demonstrated total serum bilirubin and/or transaminase liver toxicities at some point during their treatment course (based on the National Cancer Institute Common Terminology Criteria for Adverse Edvents). The following results were based on a total of 47 procedures (as one procedure did not have post-treatment laboratory values). Total serum bilirubin toxicities as follows: 26% Grade 1 (n=12), 34% Grade 2 (n=16), and 17% Grade 3 (n=8). Grade 4 bilirubin toxicity was not observed. Transaminase toxicities as follows: 43% Grade 1 (n=20), 17% Grade 2 (n=8), 28% Grade 3 (n=13), and 2% Grade 4 (n=1). No liver toxicity based on total serum bilirubin or transaminase levels was observed after 23% and 11% of procedures, respectively. No toxicity prevented future embolotherapy in these patients. No deaths occurred within 30 days following treatment. Conclusions: Hepatic artery embolization is well tolerated in patients with underlying Gilbert’s disease and these patients should not be excluded for treatment based solely on laboratory values. Poster 85: Ipilimumab (Ipi) and Immunoembolization (IE) for Treatment of Metastatic Uveal Melanoma (UM) Hepatic Metastases K. Pan1, C. Gonsalves2, D. Eschelman3, M. Orloff5, T. Sato4. 1Radiology, Thomas Jefferson University Hospital, Philadelphia, PA; 2Interventional Radiology, Thomas Jefferson University Hospital, Philadelphia, PA; 3 Interventional Radiology, Thomas Jefferson University Hospital, Philadelphia, PA; 4Oncology, Thomas Jefferson University Hospital, Philadelphia, PA; 5Oncology, Thomas Jefferson University Hospital, Philadelphia, PA. Objective: Previous reports have shown IE to be an effective treatment for UM hepatic metastases. The purpose of this study is to determine if the effectiveness of IE

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can be enhanced with adjuvant systemic Ipi, an anticytotoxic T-lymphocyte-associated protein-4 antibody. Methods: A retrospective review was performed of 26 patients (mean, 58 years [range 31 – 78]; 12 men) with UM hepatic metastases (<20% hepatic tumor burden) treated with systemic Ipi and IE between 2012 and 2015. Ipi was given at standard dosing and schedule (3mg/kg every 21 days, 4 infusions). Lobar IE was used as a first-line liver directed therapy and performed every 4 weeks with 1,500 mcg of granulocyte-macrophage-colony-stimulating factor emulsified in ethiodized oil, and 2 million IU interleukin-2, followed by gelfoam embolization. Best radiologic response (RECIST) for hepatic/extrahepatic metastases was determined using contrast-enhanced CT and MRI after every 2 IE treatments. Overall survival (OS) and progression-free survival of liver (PFS-L) and extrahepatic (PFS-S) metastases were evaluated with Kaplan-Meier analysis. Common Terminology Criteria for Adverse Events v4.0 was used to assess toxicity. Results: Twenty-six patients underwent 132 IEs (median 4; range 2-15). Eight patients (31%) had pre-existing extrahepatic metastases. Ten patients developed extrahepatic metastases (median, 7.3 months; range 2.8-25.0) during treatment. Median survival has not been reached, however, 12 patients (46%) expired during the observation period (median OS, 16.5 months; range 2.5-31.1); (95% CI, 6.4 to 22.5 months). Partial response with regression of hepatic metastases was observed in 3 patients (11.5%). Median PFS-L was 5.9 months (range, 1.7-12.2); (95% CI, 2.8 to 7.6 months). Median PFS-S was 6.9 months (range, 1.7-25.0); (95% CI, 3.5 to 12.8 months). No regression of extrahepatic metastases was observed in any patient. Most common toxicities noted included diarrhea tG2 (19.2%); rash/pruritus tG2, (19.2%); and hypothyroidism tG2, 4/26 (15.3%). Hepatic toxicity was observed in 4 patients: G1 (3.8%), G2 (7.7%) and G3 (3.8%). No G4/G5 toxicity was seen. Conclusions: Combination treatment with IE and Ipi is a feasible approach for patients with metastatic UM. However, compared to historical controls, the addition of Ipi did not appear to prolong PFS-L and PFS-S. In addition, toxicities not previously seen with IE alone were observed. Therefore, initial results do not support the use of Ipi in patients undergoing IE. However, future randomized studies comparing combination therapy versus IE alone may be warranted. Poster 86: Hepatic Intra-Arterial Infusion Chemotherapy Plus Systemic Chemotherapy for Unresectable Synchronous Multiple Liver Metastases from Colorectal Cancer K. Hayano1, G. Ohira1, H. Miyauchi2, T. Tohma3, H. Matsubara1, K. Shuto4. 1Department of Frontier Surgery, Chiba University Graduate School of Medicine, Chiba, Japan; 2Department of Frontier Surgery, Chiba University Graduate School of Medicine, Chiba, Japan; 3 Department of Frontier Surgery, Chiba University Graduate School of Medicine, Chiba, Japan; 4Department of Surgery, Teikyo University Chiba Medical Center, Ichihara, Japan. Objective: Studies of hepatic intra-arterial infusion chemotherapy (HAIC) demonstrated significant tumor response rates. The purpose of this study is to evaluate usefulness of HAIC plus systemic chemotherapy in unresectable synchronous multiple liver metastases from colorectal cancer (CRC). Methods: We retrospectively identified 25 patients with unresectable synchronous multiple liver metastases (t 7 metastases) from CRC between June 2004 and July 2012. All patients received surgery for primary CRC, and 11 patients were subsequently treated with HAIC (5FU) plus systemic chemotherapy (CPT-11) (group A), and 14 with systemic chemotherapy alone (group B). The best percent change of the liver metastases was assessed according to RECIST 1.1. Overall survival (OS) was compared between group A and B. Results: The median duration of HAIC+CPT-11 treatment was 6.5 months (from 3.5 to 11.7). Catheter troubles occurred in three patients (27%). The best percent change of the liver metastases from baseline was –38.4% (from –9.0 to –82.0%), and tumor control rate was 100% (partial response, 6 cases; stable disease, 5) in patients treated with HAIC+CPT-11. In Kaplan-Meyer analysis, group A showed a better OS than group B (Figure 1), but it was not statistically significant (P=0.06). The 1-year survival rate was 90.9% for group A and 64.2% for group B, and the 2-year survival rate was 45.4% for group A and 24.1% for group B. In group A, 5 patients had extrahepatic metastases (lung or lymph nodes), and the median survival time of these patients was 19.7 months, while the median survival time of 6 patients without extrahepatic metastases was 33.7 months. Conclusions: HAIC+CPT-11 shows a high tumor control rate in the liver metastases, and has a potential to be the first line treatment option for unresectable synchronous multiple liver metastases from CRC. Especially, HAIC+CPT-11 would be recommended for patients without extrahepatic metastases.

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Poster 87: Comparison of Contralateral Lobar Hypertrophy Achieved by Unilobar Y-90 Radioembolization vs. Portal Vein Embolization in Patients with Colorectal Liver Metastases K. Stewart, V. Khanna, A. Sharma, A. Katz. University of Rochester, Pittsford, NY. Objective: To examine and compare contralateral lobar hypertrophy in patients with colorectal liver metastases undergoing unilobar Y-90 radioembolization (Y-90) versus portal vein embolization (PVE). This is the first direct comparison of radioembolization verus PVE that the authors are aware of. Methods: Patients with colorectal liver metastases who underwent unilobar Y-90 (contralateral lobe either not treated or at least 6 months between treatments) or PVE at our institution between 2009-June 2015 were identified. Patients with pre and post procedural CECT and CE MRI were included. Volumetric functional lobar liver volumes excluding tumor, vessels and biliary structures were calculated on CT and MRI. Future liver remnants (FLR= Untreated Lobe /Total functional liver volume) of both groups were calculated at 1-3, 3-6, and 6-9 months and compared to baseline using Wilcoxon signed rank test. The 3-6 and 6-9 month FLRs for the Y-90 patients were compared to the 1-3 month results for PVE patients using the Mann-Whitney test. Results: 10 patients (6M/4F) underwent unilobar (3 left/7 right) Y-90. 2 patients had contralateral lobe treatment 210 and 385 days after initial treatment. FLR (ml) in Y-90 group at baseline and at 1-3, 3-6 and 6-9 months compared to baseline were 37.9(13.2-95.7), 53.9(17.5-91.9) p 0.16, 53.2(47.7-97.1) p 0.06, 62.1(21.6-98) p 0.13. Percentage FLR increase from baseline at 1-3, 3-6 and 6-9 months 17.9%(-4-41.3) p 0.16, 28.7%(1.5-79.5) p 0.06, 24.7%(-4-153.3) p 0.13. 7 patients(4M/3F) had right lobe PVE. FLR in PVE group at baseline and 1-3 months was 33.5(10.1-44.2) and 36(15.9-56) p 0.03. FLR percentage increase from baseline at 1-3 months was 33.1%(1.4-64.7) p 0.03. FLR percentage increase in Y-90 group at 1-3, 3-6, and 6-9 months compared with PVE group at 1-3months from baseline were 17.9(-4-41.3) and 33.1(1.4-64.7) p 0.31, 28.7(1.5-79.5) and 33.1(1.4-64.7) p 0.93, 24.7(-4-153.3) and 33.1(1.4-64.7) p 0.66. Conclusions: In patients with colorectal liver metastases PVE results in early FLR hypertrophy that is statistically significant. Unilobar Y-90 results in a slower FLR hypertrophy which tends to increase with time with near statistical significance at 3-6 months. There is no significant difference in hypertrophy when comparing Y-90 to the early hypertrophy achieved by PVE. Poster 88: Treatment Response of Neuroendocrine Hepatic Metastases After Y-90 Radioembolization Based on Imaging and Chromogranin A Levels K. Stewart1, V. Khanna2, A. Sharma3, A. Katz4. 1University of Rochester, Pittsford, NY; 2University of Rochester, Rochester, NY; 3University of Rochester, Rochester, NY; 4University of Rochester, Rochester, NY. Objective: Evaluation of the response to treatment after Y-90 radioembolization of hepatic metastases from neuroendocrine tumors by evaluating the imaging response and pre and post treatment chromogranin A levels. Methods: Records of Y 90 radioembolizations for neuroendocrine hepatic metastases at a single institution were reviewed from 2011 to July 2015. The imaging pre and post treatment was reviewed and categorized as complete response, partial response, stable disease, or progressive disease. The 3 month averages of pre and post treatment chromogranin A levels were recorded and evaluated for treatment response. Data was also collected for side treated, follow up treatments, primary tumor location, tumor grade, extrahepatic metastases, and primary tumor resection prior to radioembolization. Results: Twenty patients underwent radioembolization for neuroendocrine hepatic metastases. 10 male and 10 female. Based on imaging 12 patients had a partial

Poster 89: Bland Transarterial Embolization of Neuroendocrine Tumor Liver Metastases: Clinical and Imaging Outcomes A. Jaberi, O. Mironov, J.R. Kachura. Medical Imaging, Toronto General Hospital, Toronto, ON, Canada. Objective: To assess clinical efficacy, medical imaging outcomes, and procedural variables of bland transarterial embolization (TAE) for the treatment of neuroendocrine tumor (NET) hepatic metastases. Methods: Retrospective single arm cohort study of patients at a tertiary care center undergoing TAE of NET metastases from 07/1999 to 08/2015. Clinical data and imaging were evaluated pre-admission and at 3-6 month intervals post-TAE. Outcomes assessed included overall survival (OS), progression free survival (PFS) using mRECIST criteria, and symptomatic improvement. Subgroup analysis and survival comparison were performed using chi-square analysis and log rank test, respectively. Results: 50 patients (23 males, 27 females) underwent 98 TAE using polyvinyl alcohol or trisacryl gelatin microspheres. Median time to TAE from hepatic metastases diagnosis was 804 days. Median follow-up after TAE was 515 days. Median length of hospital stay was 4 days. 1 patient died within 30 days of TAE due to disease progression. There were 7 (7.2%) major and 5 (5.0%) minor procedural complications, with no significant difference between second simultaneous bilobar (10) vs uni-lobar (22) TAE (p = 1.00). Cumulative PFS rates at 3, 6, 9, 12, 15, and 18 months were 75, 49, 32, 25, 20, 12% with a median of 5.7 months. Cumulative OS rates at 1, 2, 3, 4, and 5 years were 80, 63, 40, 33, 29% with a median of 2.6 years. Patients with prior primary tumor resection had significantly improved OS (p=0.029, HR=0.42, 95% CI 0.18-0.93). There was no significant difference in PFS or OS comparing length of time from diagnosis of hepatic metastases to TAE, NET vs. carcinoid tumours, primary tumor location, documented extrahepatic metastases, prior hepatic metastasectomy, or octreotide analogue treatment. 27 of the 33 symptomatic patients (81.8%) undergoing TAE experienced improvement. Conclusions: Bland transarterial embolization (TAE) results in symptomatic and radiologic response in most patients with NET hepatic metastases. Bilobar embolization during a second TAE may be considered a safe option. PFS and OS were found to be comparable to currently published literature. Prior resection of the primary tumor was associated with significantly improved OS. Poster 90: Renal Cell Carcinoma Metastatic to the Liver: Early Response Assessment after Intraarterial Therapy using 3D Quantitative Tumor Enhancement Analysis F.N. Fleckenstein2, R. Schernthaner1, R. Duran3, J. Ho Sohn3, S. Sahu3, Y. Zhao3, M. Lin3, J. Chapiro3, R. Salem4, J. Geschwind3. 1Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; 2Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany; 3Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT; 4Radiology, Northwestern University, Chicago, IL. Objective: Liver metastases from renal cell carcinoma (RCC) are not uncommon in the course of disease and occur in over 20% of patients. Intraarterial therapy (IAT) is a treatment option for patients with liver dominant metastases. However, data about tumor response is scarce. This study assessed whether volumetric changes of enhancing tumor after one session of IAT using quantitative EASL (qEASL) on magnetic resonance imaging (MRI) and computed tomography (CT) can evaluate tumor response and predicts overall survival (OS). Methods: 14 patients (6 female, mean age 66) with liver dominant metastatic RCC treated with IAT (TACE, n=9 and Y-90, n=5) were retrospectively included. All patients underwent contrast-enhanced imaging (MRI, n=10 and CT, n=4) 3-4

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response to treatment, 5 patients had stable disease, and 3 patients had progressive disease. Of the treated patients 10 patients had documented chromogranin A levels 3 months prior to treatment and 3 months after treatment. 80% of those patients had a decrease in their chromogranin A levels. The average decrease in chromogranin A levels was 51%. The 20% of patients with an increase in chromogranin A levels had an average increase of 80%. Of the patients with increased chromogranin A levels post procedure one had resection of the primary pre radioembolization and one did not. Both of the patients with elevated chromogranin A levels post procedure showed a partial response on follow up imaging, both had pancreatic primary tumors, one was well differentiated and the other tumor grade was unavailable. Of those with reduced chromogranin A levels post procedure imaging showed 4 with partial response, 2 had stable disease, and 2 had progressive disease. The initial radioembolization was on the right in 16 patients, left in 3 patients, and bilateral in 1 patient. The contralateral lobe was subsequently treated in 13 patients. Conclusions: Imaging response and chromogranin A levels before and after radioembolization treatment are useful indicators of response to therapy and the combined results offer more complete information than each indicator by itself.

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weeks pre- and post-treatment. Response to treatment was evaluated on the arterial-phase using Response Evaluation Criteria in Solid Tumors (RECIST), World Health Organization (WHO), modified RECIST (mRECIST), European Association for the Study of the Liver (EASL), tumor volume (vRECIST) and volumetric tumor enhancement (qEASL). A 3D semi-automatic segmentation software was used to obtain qEASL[cm3] (enhancing tumor volume) and qEASL[%] (percentage of enhancing tumor volume) values. Paired t-test was used to compare measurements pre- and post-IAT. For qEASL ([cm3] and [%]) assessment, patients were stratified into responders (R, t65% decrease in qEASL) and non-responders (NR, <65% decrease in qEASL). OS of R and NR was evaluated using Kaplan-Meier curves with log-rank test and the Cox proportional hazard model. Results: Mean qEASL [cm3] decreased from 93.5 to 67.2cm3 (p=0.004) and mean qEASL [%] from 63.1 to 35,6% (p=0.001). No significant changes were observed using other response criteria. qEASL was the only significant predictor of OS when used to stratify patients into responders and non-responders with median OS of 31.9 months vs. 11.1 months (HR 0.43; 95% CI, 0.19-0,97; p=0.042) for qEASL [cm3] and 29.9 months vs. 10.2 months (HR 0.09; 95% CI, 0.01-0.74; p=0.025) for qEASL [%]. Conclusions: 3D quantitative tumor analysis is a strong predictor of OS when assessing treatment response after IAT in patients with RCC metastatic to the liver. qEASL outperforms conventional non-3D methods and can be used as a surrogate marker for OS early after therapy.

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p=0.011) and was identified as a risk factor (CT: p=0.009, ICC: p=0.001) in the UVA. Age of <70 years was predictive (MVA for CT: p=0.001, for ICC: 0.042) for better OS independently of IAT type (40.6 vs. 15.5 mos, p=0.002). Patients with NELMs recurrence after initial radio frequency ablation or liver resection with curative intent had a significantly longer OS when treated with cTACE as compared to DEB-TACE or 90YRE (21.9 vs. 5.9 vs. 7.8 mos, p=0.001). Patients who underwent t3 cTACE sessions had a prolonged OS compared with patients with d 2 sessions (45.5 vs. 17.5 mos, p=0.013). The number of embolizations was predictive of survival for patients with ICC (MVA: p=0.018), but not for CT. Conclusions: Patients with NET metastatic to the liver had greater OS after receiving cTACE compared with patients who underwent DEB-TACE and 90YRE, if subject to the criteria: TB of <50%, lesion diameter <5cm, and 2-5 lesions. Overall, cTACE can thus be seen as the modality of choice in patients with hepatic NET metastases.

Poster 92: Comparison of Cone-Beam Computed Tomography (CBCT) and Cross-Sectional Imaging (CSI) for Volumetric and Dosimetric Calculations in Resin Yttrium-90 (Y-90) Radioembolization Poster 91: Comparing cTACE, DEB-TACE and 90Y Radioembolization as Treatment Options for Patients with Neuroendocrine Tumor Metastatic to the Liver D. Do Minh2, J. Chapiro3, S. Smolka2, M. Lin4, D. Wainstejn2, B. Gorodetsk1, L.J. Savic1, T. Schlachter2, B. Gebauer5, J. Geschwind6. 1 Charite University Hospital Berlin, Berlin, Germany; 2Department of Radiology and Biomedical Imaging, The Yale University School of Medicine, Berlin, Germany; 3Radiology, Charité University Hospital, Berlin, Germany; 4Philips Research North America, Cambridge, MA; 5 Radiology, Charité University Hospital, Berlin, Germany; 6Department of Radiology and Biomedical Imaging, The Yale University School of Medicine, Yale, CT. Objective: To compare the efficacy and survival outcome of conventional transarterial chemoembolization (cTACE), drug eluting beads TACE (DEB-TACE), and 90Yttrium radioembolization (90YRE) as treatment options for patients with gastro-entero-pancreatic neuroendocrine liver metastases (NELMs) and to determine the prognostic variables that influence the survival in patients after receiving cTACE, DEB-TACE, or 90YRE. Methods: In this retrospective single center study, 192 patients with NELMs of known gastro-entero-pancreatic origin who received treatment with cTACE (N=122), DEB-TACE (N=26), or 90YRE (N=44) without therapy cross-over between 2000 and 2013 were included. The patient group contained 125 patients with carcinoid tumors (CT) and 67 patients with pancreatic islet cell carcinomas (ICC). Overall survival (OS) was calculated using the Kaplan-Meier method with log-rank test. Univariate (UVA) and multivariate (MVA) analyses were performed to determine prognostic variables affecting survival. Results: Regardless of the type of intraarterial therapy (IAT), MVA identified liver tumor burden (TB) of >50% as an independent risk factor for poor survival (cTACE: p=0.001, DEB-TACE: p=0.013, 90YRE: p=0.006). In patients with TB <50%, cTACE and 90YRE was superior over DEB-TACE (47.1, 40.0 vs 21.2 mos, p=0.001). Lesion diameter <5cm was predictive for OS in the UVA (CT: p=0.002; ICC: p=0.035) but not in the MVA. cTACE improved the OS in patients with metastasic lesions with diameter of <5cm compared to DEB-TACE and 90YRE (48.5 vs. 22.0 vs. 29.8 mos, p=0.0013). A statistically significant improvement of survival in patients with 2 to 5 lesions who underwent cTACE or 90YRE was observed compared with patients who underwent DEB-TACE (OS: 47.1, 47.8 vs. 10.2 mos, p=0.001). For patients with >5 lesions, no statistically significant difference between the modalities was reached. The presence of extra-hepatic metastases reduced the OS (41.4 vs. 28.8 mos,

H. Choi1, J. Lischalk2, T. Caridi1, G.E. Lynskey1, K. Unger2, A.Y. Kim1. 1 Dept of Radiology, Medstar Georgetown University Hospital, Washington, DC; 2Radiation Oncology, Medstar Georgetown University Hospital, Washington, DC. Objective: Traditional dosimetric calculations for Y-90 radioembolization are based on hepatic volumes calculated from CSI. CBCT is a technique that can be used to better define actual perfused volume. We compare the volumetric and dosimetric calculations obtained from standard CSI with those from CBCT. Methods: Mapping angiograms were obtained prior to radioembolization in 27 patients undergoing treatment for primary or secondary liver malignancies from July 2015 to November 2015. CBCT was obtained on a Siemens Artis Zee unit (Munich, Germany) in a standard lobar fashion (Omnipaque 350, GE health care, NJ). Perfused lobar volumes were then acquired using the volume calculation software provided by Siemens. Standard volumetric data was also obtained for each patient with Varian Eclipse contouring software, utilizing the most recent abdominal CT or MRI. Total liver and tumor volumes were acquired from CSI only. Nominal activities were then calculated with both CBCT- and CSI-acquired volumes, using SIR-Spheres Microspheres Activity Calculator (SMAC). Volumetric and dosimetric data were compared using the student’s T-test (two-tailed, paired). Results: 27 patients with a total of 46 hepatic lobes were evaluated for radioembolization. The difference in measured volumes between CBCT and CSI ranged from 0.6-75.9% (mean 19.5%) for the right lobe and 1.9-142.9% (mean 27.6%) for the left lobe. The difference in calculated Y-90 activity for the right and left lobes using the two methods ranged from 0.9-75.8% (mean 19.6%) and 2.6-143.9% (mean 29.0%). There was a calculated dose difference of >10% in 26 of 46 lobes evaluated (57%). 14 lobes (30%) had >25% difference in calculated dose and a difference of >50% in 4 lobes (9%). Conclusions: We found a large difference in dose calculations utilizing volumes obtained from CSI and CBCT in a majority of studied patients. Further evaluations are needed to assess if CSI or CBCT is the preferred method to calculate liver volumes for dose calculations.

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Poster 93: Correlation of Tumor Contrast Uptake on Cone-Beam CT and Tumor Response After Transarterial Radioembolization N. Kim1, A.Y. Kim2. 1Department of Radiology, Medstar Georgetown University Hospital, Washington, DC; 2Dept of Radiology, Medstar Georgetown University Hospital, Washington, DC. Objective: There are no reliable predictors of outcomes after transarterial radioembolization (TARE) for patients with secondary liver cancers. The hypothesis for this study is to determine if tumor response is correlated with the degree of contrast uptake demonstrated on cone-beam CT (CBCT) during mapping angiogram. Methods: Retrospective evaluation was performed of 20 patients who underwent TARE for liver metastases secondary to colorectal cancer. Seven patients were excluded from the study due to diffuse metastatic disease without identifiable discrete liver lesions. Contrast enhancement in Hounsfield units (HU) of metastatic lesion and normal liver were measured on CBCT obtained during mapping angiogram. All CBCT were performed with a 6 second imaging delay. Tumor response was determined by the RECIST criteria based on the three to six month follow up CT. Correlation coefficients were calculated looking at tumor contrast uptake on CBCT and tumor response based on RECIST criteria, and difference in lesion size and contrast uptake. Results: A total of 19 lesions in 13 patients were evaluated. A single lesion was evaluated in 8 patients, 2 lesions evaluated in 4 patients, and 3 lesions evaluated in 1 patient. The average HU of background liver and tumor were 37.7 (range -422 to 186) and -18.1 (range -436 to 138) respectively. Nine lesions had a decrease in tumor diameter, 2 lesions had no change, and 8 lesions increased in size after treatment. One lesion had partial response, sixteen lesions had stable disease and two lesions had disease progression based on RECIST criteria. Five lesions in two patients demonstrated increased tumor perfusion over background liver demonstrating difference of 74, 21, 125, 92 and 4 HU over background liver. Four of the five lesions had a decrease in size in follow up imaging, ranging from 0.2–1.0cm. The fifth lesion was stable in size. The correlation coefficient of contrast uptake on CBCT and tumor response was R=0.5 (p=0.19). The correlation coefficient of change in tumor size and tumor enhancement was R=-0.15 (p=0.13). Conclusions: We found no statistically significant correlation between tumor perfusion and disease response. However, all five lesions with increased tumor perfusion compared to background liver demonstrated disease control, including decrease in tumor diameter demonstrated in 4 lesions. The lack of statistical significance may be due to the low number of lesions evaluated. Further evaluations are needed for validation. Poster 94: Predictors of Metabolic Tumor Response After Y 90 Radioembolization of Colorectal Liver Metastases W. Shady1, S. Kishore2, S. Gavane2, V.S. Sotirchos1, E.N. Petre1, J. Osborne2, R.K. Do4, M. Gonen3, E. Ziv1, F.E. Boas1, H. Yarmohammadi1, R.H. Siegelbaum1, L.A. Brody1, A. Cercek5, N.H. Segal5, N.E. Kemeny5, C.T. Sofocleous1. 1Interventional Radiology, Memorial Sloan Kettering Cancer Center, New York, NY; 2Nuclear Medicine, Memorial Sloan Kettering Cancer Center, New York, NY; 3 Epidemiology-Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY; 4Radiology, Memorial Sloan Kettering Cancer Center, New York, NY; 5Medicine, Memorial Sloan Kettering Cancer Center, New York, NY. Objective: To evaluated predictors of the percentage change of metabolic activity (SUVmax) and metabolic response (SUVmax) post Y90 radioembolization (RE) of colorectal liver metastases. Methods: We performed a retrospective review of our clinical Y90 RE database for patients with unresectable CLM treated with SIR-spheres between December 2009 and December 2013. We included patients who had PET/CT scans at baseline and

on the 1st follow-up post-RE. The percentage change in SUVmax was calculated for each tumor and a cut-off point of >30% decrease was chosen to define response. Several clinical, technical, and imaging factors were evaluated as predictors. Tumor enhancement on CT arteriogram (CTA) performed during hepatic arteriogrpahy mapping was classified into non-enhancing, enhancing margin, and entirely enhancing. Generalized estimating equations adjusted for clustering were used to evaluate for significance in predicting the percentage change in SUVmax. Logistic regression adjusted for clustering was used to detect significance in predicting tumor metabolic response (>30% decrease in SUVmax). Results: The study enrolled 51 patients with 126 tumors; a median of 2 (range: 1-5) tumors. On univariate analysis predictor of the percentage change in SUVmax were: tumor enhancement pattern on CTA (P<0.001), metabolic tumor volume >65cc (P=0.07), systemic chemotherapy post-RE (P=0.086), CEA >200 ng/ml (P=0.058), and Kras mutation (P=0.032). Lack of full dose delivery due to stasis (P=0.5) or the percentage of the delivered dose <75% (P=0.7) were not significant predictors. On multivariate analysis, post-RE chemotherapy (P=0.001), Kras mutation (P=0.04), and tumor enhancement pattern (P<0.001) were independent predictors of the percentage change of SUVmax. For metabolic tumor response (>30% decline in SUVmax), only the enhancement pattern was a statistically significant predictor: enhancing margin (P=0.012), entirely enhancing (P=0.018). Conclusions: Receiving systemic chemotherapy post-RE, kras wild type tumors, and tumor enhancement are independent predictors of a greater percentage decrease in SUVmax post-RE of CLM. Poster 95: Radiofrequency Ablation for Colorectal Liver Metastases (CRLM): Experience from a Single Tertiary Care Centre from India P.G. PATEL1, S. Kulkarni1, N. Shetty1, A. Polnaya1, S. Patil3, R.S. Chivate3, K. Gala2, V. Bakre3, M. Goel4. 1INTERVENTIONAL RADIOLOGY, TATA MEMORIAL HOSPITAL, MUMBAI, India; 2Radiology, Tata Memorial Centre, Mumbai, India; 3Interventional Radiology, Tata Memorial Hospital, Thane, India; 4Surgical Oncology, TATA MEMORIAL HOSPITAL, Mumbai, India. Objective: To evaluate role of Radiofrequency ablation in the treatment of unresectable colorectal liver metastases. Methods: Retrospective analysis of prospectively maintained data was done. A total 86 patients with unresectable CRLM underwent 124 sessions RFA at our institute from January 2010–June 2015. Analysis was done from clinical, biochemical data, and imaging (PETCT/MRI) characteristics were obtained at baseline, 6 weeks and 3 months and every 6 months thereafter. Response evaluation was performed according to Modified RECIST 1.1 criteria. The clinical and laboratory toxicity post-treatment was assessed by the Common Terminology Criteria Adverse Events (CTCAE) version 3.0 Results: 86 patients with unresectable CRLM underwent 124 sessions RFA with median follow up duration- 495 days (range 130-1795 days). Complete ablation of liver lesion was achieved in 77/86 (89.5%) at Day 1 and 63/81 (77.7%) at 3 months. 5 patients were lost to follow-up after initial ablation and three patients were lost to follow-up after six months. Local recurrence was seen 3 (3.8%). Progression was noted in 15 patients (6 Hepatic, 9 Extra-hepatic sites. Median progression free survival (PFS) was 12.6 months. Median survival rate at 1 and 3 years was 94.3% and 55.6% while overall survival was 42.3 months. No major complication seen in our series Conclusions: RFA is safe and effective in treatment of unresectable colorectal liver metastases and results are on par with global standards Poster 96: Thermal Ablation of Hepatic Metastases from Breast Carcinoma T.D. Howard, A.N. Kurup, G.D. Schmit, T.D. Atwell, D.A. Woodrum, J.J. Schmitz, A.J. Weisbrod, M. Callstrom. Radiology, Mayo Clinic, Rochester, MN. Objective: To investigate the safety and clinical impact of percutaneous or intraoperative ablation of breast cancer liver metastasis on progression of disease. Methods: All patients who underwent image (US/CT)-guided radiofrequency, microwave, and/or ethanol ablation of a breast cancer liver metastatic lesion over a 15-year period (2000-2015) were retrospectively identified using an internally maintained clinical registry. Patients were followed with contrast-enhanced CT, MRI or PET/CT to detect local tumor recurrence at the ablation site, recurrent regional (liver-specific) metastatic disease, or new remote metastatic disease outside the liver. Progression-free timeframes were calculated. Hospital stays were recorded, and complications within 30 days of the ablation procedure were graded using the Clavien-Dindo classification. Results: Thirty-five metastatic breast cancer liver lesions were treated in 24 patients. Six (17%) tumors showed local recurrence in 6 (25%) patients discovered at a mean of 7.7 months. Fourteen (58%) patients developed regional metastases within the liver at 21.5 months, and 16 (67%) patients developed distant metastases outside the liver at 16.1 months. There was no correlation with chemotherapy agent used at the time of

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ablation or breast cancer hormone receptor status. Average length of hospital stay was one evening. There were three grade 2 complications, including brachial plexopathy, hepatic vein thrombus, and pneumonia thought to be due to splinting from right upper quadrant pain. There were no deaths within 30 days of the procedure. Conclusions: Image-guided ablation is safe and moderately effective to control local breast cancer liver metastases. However, most patients show recurrent metastases within or outside the liver within two years.

Conclusions: Interventional oncology in pediatric age group is an evolving specialty. Our experience demonstrates that these procedures are feasible and provide a safe and minimally invasive treatment and/ or palliative option in clinical care of children with cancer.

Poster 97: Yttrium-90 Radioembolization for the Treatment of Hepatic Metastases from Pulmonary Neuroendocrine Tumors: A Safety and Efficacy Study

C. Pusceddu1, N. Ballicu1, A. Fancellu2, L. Melis1. 1Department of Oncological Radiology, Oncological Hospital “A. Businco”, Cagliari, Italy; 2Department of Clinical and Experimental Medicine, Unit of General Surgery, Sassari, Italy.

A.J. Gonzalez Aguirre1, V.S. Sotirchos1, W. Shady1, E.G. Violari1, N. Pandit - Taskar1, R.K. Do2, M. Gonen3, W. Alago1, R.H. Siegelbaum4, H. Yarmohammadi5, F.E. Boas6, S.B. Solomon7, M.C. Pietanza1, C.T. Sofocleous8. 1Memorial Sloan Kettering Cancer Center, New York, NY; 2Memorial Sloan Kettering Cancer Center, New York, NY; 3Memorial Sloan Kettering Cancer Center, New York, NY; 4Memorial Sloan Kettering Cancer Center, New York, NY; 5Memorial Sloan Kettering Cancer Center, New York, NY; 6Memorial Sloan Kettering Cancer Center, New York, NY; 7Memorial Sloan Kettering Cancer Center, New York, NY; 8Memorial Sloan Kettering Cancer Center, New York, NY. Objective: To examine the safety and efficacy of yttrium-90 radioembolization (RE) with resin microspheres for the treatment of hepatic metastases from pulmonary neuroendocrine tumors. Methods: An IRB waiver was obtained to retrospectively review treatment parameters and patient outcomes after RE for hepatic metastases from neuroendocrine lung tumors. Response to treatment was assessed by evaluating changes in size (RECIST 1.0) and metabolic activity (EORTC criteria) of the target lesions. Complications and toxicities within the first 30 days were evaluated according to the NCI CTCAE v4.0. Kaplan-Meier methodology was used to calculate liver progression-free (LPFS) and overall survival (OS). Results: From August 2010 to November 2015, 25 patients (median age: 63 years) with hepatic metastases (primary tumor; small cell=13, large cell=2, atypical carcinoid=8, typical carcinoid=2) received a total of 45 sessions of RE. Median OS for the entire group was 13.2 months (95% CI: 2.8 – 23.5). For patients with high grade tumors (small/large cell) OS was 4.3 months (95% CI: 2.5-6.1) and 44 months (95% CI: 44.2 – 47.6) for patients with low grade tumors (atypical and typical carcinoids) (p<001). 1 death was noted in the low grade tumor group after a mean follow-up time of 45 months (p=0.003). Overall median LPFS was 6.3 months (95% CI: 4.1 – 8.4). Median LPFS was 3.7 months in the high grade tumor group vs. 20.5 months in the low grade group (p=0.001). Response to RE was evaluated after 4-8 weeks. Of the 23 patients with available CT exams, 11 patients exhibited partial response, 11 had stable disease and 1 disease progression. Of the 21 patients with PET/CT exams, 17 had response within the treated liver volume. The majority of patients (85%) experienced mild (grade 1-2) clinical toxicities within the first 30 days. Other significant toxicities included decreased lymphocyte counts (grade 3) after 32% of sessions, one case of hyponatremia (grade 4) and one case of thrombocytopenia (grade 3). 22 patients resumed systemic chemotherapy post-RE. Conclusions: RE for hepatic metastases from pulmonary neuroendocrine tumors was relatively well-tolerated and provided in the majority of cases initial response. A wide range of outcomes was observed depending on tumor histology. Additional studies are necessary to demonstrate any potential benefit of RE for chemorefractory hepatic disease.

Poster 101: Percutaneous Pedicle Screw Fixation Followed by Cementoplasty: A Minimally Invasive Technique for Metastatic Spinal Disease

Objective: To retrospectively evaluate the feasibility and effectiveness of CT-guided percutaneous screw fixation plus cementoplasty (PSFPC) in patients with painful vertebral metastases with fractures or to prevent pathological fracture. Methods: Sixteen patients (5 men and 11 women, median age 54 years) with 20 vertebral metastases (8 NSCLC, 6 multiple myeloma, 5 breast carcinoma and 1 thymoma) underwent CT–guided PSFPC. The procedure was performed in a single vertebra in 12 patients and in two vertebrae in 4 patients. The vertebral approach was unilateral with a single screw in nine patients and bilateral with two screws in the remaining 7. Eight patients underwent microwave tumor ablation (MWA) before the osteosynthesis. We analyzed the feasibility and complications of the procedure, the decrease in pain using a visual analogue scale (VAS) and the functional outcome assessed according to the evolution of their walking ability. Results: Pain relief was observed just one week from the treatment in all patients. VAS score decreased from 7.1(range, 4- 8.7) to 1.3(range, 0-4). There were no complications related to infections or incorrect positioning of the screws or leakage of cement. All patients were able to walk within 6 hours after the procedure and have improved their walking capacity at six months. No new bone fracture occurred during a median follow-up of 9 months. Conclusions: Our results suggest that PSFPC is a safe and effective procedure which allows us to stabilize the vertebral fracture and prevent pathological fractures with significant pain relief and good recovery of walking ability.

Poster 100: Oncological Interventions In Pediatric Patients R. Shaikh. Interventional Radiology, Boston Childrens Hospital, Boston, MA. Objective: While the use of interventional techniques to treat adult oncology patients is well established, the translation of these techniques to the pediatric realm continues to evolve. Interventional approaches provide a valuable alternative for disease treatment and symptom management. The pioneering use of interventional techniques to treat and palliate oncologic disease in pediatric patients is overdue. We evaluated pediatric patients who underwent different interventional procedures for cancer treatment or palliation at our institution. Methods: We retrospectively reviewed the medical records and imaging studies of all pediatric patients with cancer who underwent interventional procedures e.g. cryoablation, radiofrequency ablation, sclerotherapy and transarterial embolization at our institution. Patient and disease demographics, interventional procedures performed and outcomes were documented. Symptomatic and radiological changes were evaluated and compared pre and post procedure. Results: Thirty patients (5-20 yrs.; mean age 12.5 yrs.) underwent interventional oncological procedures for different indications. The outcome of these interventions was individually evaluated at procedural level.

Fig 1 CT scan shows multiple fractures of large metastasis of T10.

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M. Lin, X. Xie. Department of Medical Ultrasound, Institute of Diagnostic and Interventional Ultrasound, Guangzhou, China.

Fig 2 CT scan performed after bilateral pedicle screw fixation. Poster 102: The Highest Cited Articles in Interventional Oncology: Where are They Published and By Whom? N. Kokabi1, M. Xing2, J.C. Camacho1, H.S. Kim2. 1Interventional Radiology and Image Guided Medicine, Emory University Hospital, Atlanta, GA; 2Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT. Objective: To identify highly cited articles in interventional oncology (IO) and to analyze the range of topics, the publishing journals and the authors’ credentials Methods: Using Web of Science™ (Thompson Rueters, New York, NY) database, papers with t100 citations published up to October 1, 2015 that either directly evaluated an IO therapy or recommended an IO modality as a treatment option were included. Various search permutation were used, including chemo/radio embolization and thermal ablations in several organs including liver, kidney, lung, and bone. The journals’ focus and impact factor, the disease topic as well as geographic location and specialty of the corresponding author were then analyzed. Results: A total of 286 papers with t100 to 2982 citations were identified. All articles were published between 1987 and 2012 in 42 individual journals (8 radiology journals). The median number of citations was 246 with median impact factor of 7.34 (range: 1.52-55.87). The mean number of citation was higher in non-radiology (264) vs. radiology (220) journals (p<0.001). There were 6 papers with t1000 citations, all published in non-radiology journals and about HCC chemoembolization or treatment algorithm including IO. RFA with 122 (43%) was the most published modality followed by chemo and radio embolization with 81(28%) and 19 (7%) papers respectively. One hundred fifteen (40%) of papers were published in radiology journals, followed by 43(15%) in surgery, 38 (13%) in oncology, 26 (9%) in hepatology, and 21 (7%) in urology journals. Among articles in radiology journals, only 14 (5%) were published in interventional radiology journals. Among the 20 highest cited articles, 14 papers were published in non-radiology journals. There were 131 (45%) corresponding authors from USA, 86 (30%) from Europe, and 64 (22%) from Asia. Of these, 137 (48%) were radiologists with 54 (19%) surgeons, 40 (14%) hepatologists, and 18 (6%) urologists. Conclusions: A large proportion of highly cited IO articles are published in a small number of non-radiology journals predominantly reflecting the specialty of the corresponding authors. Collaboration with other specialties could be beneficial in publishing research in high impact journals.

Objective: To evaluate the risk factors of intrahepatic biliary complications after percutaneous ablation of malignant liver tumors (MLTs), and to evaluate the minimum safe distance from the bile duct for ablation of an abutting tumor. Methods: Sixty five patients with intrahepatic biliary complications after percutaneous ablation of MLTs, and 65 controls were retrospectively recruited. Patient characteristics were collected and evaluated. Tumor location was recorded as d5 mm (group A), 5-10 mm (group B) and >10 mm (group C) from the first or second bile duct branch. An independent sample t-test or Chi-square test was used for identifying the significant risk factors for intrahepatic biliary complications. Independent risk factors were determined by odds ratio (OR) with logistic regression analysis. Results: A Chi-square test revealed that pre-ablation ascites(P<0.001), TACE treatment history(P=0.025), intrahepatic bile duct dilatation(P<0.001), and tumor location (P=0.000)were significant risk factors for intrahepatic biliary complications. Further assessment of tumor location revealed that the risk of intrahepatic biliary complications was significantly different between groups A and C (P=0.000), and between groups B and C (P=0.000); significant differences were not found between groups A and B (P=0.751). Multivariate analysis showed that pre-ablation ascites(P=0.002), and tumor location(P<0.001)were independent predictors for intrahepatic biliary complications with the OR (95% confidence interval) of 39.31(3.95-391.69) and 16.56 (5.87-46.71), respectively. Conclusions: Pre-ablation ascites and tumor location were independent risk factors for intrahepatic biliary complications after percutaneous ablation of MLTs. Intrahepatic biliary complications after treatment were the result of local treatment-related factors combined with the general condition of the patient. The minimum safe distance for ablation of tumor abutting a bile duct was 10 mm.

Fig. 1. Flowchart of for patients included in the study

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Poster 103: Risk Factors for Intrahepatic Biliary Complications After Thermal Ablation of Malignant Liver Tumors: A Retrospective Case-Control Study

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Poster 104: Interventional Oncology in Patient-Centered Online Cancer Resources: Where does IO Stand?

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M.M. Cristescu, M.C. Brunner. University of Wisconsin, Madison, WI. Objective: Efforts to rebrand interventional radiologists specializing in cancer care as interventional oncologists (IO) have grown dramatically within the interventional community in recent years. Although this may clarify the role of the inverventionalist as an oncologic specialist to patients and providers, questions remain as to whether this nomenclature has led to a wider recognition of the IO’s role in cancer therapy. Using online search analytics, we aim to evaluate the dissemination of information about available IO therapies and providers within commonly viewed patient-centered online cancer resources. Methods: In order to compile a list of commonly used search terms relating to cancer therapy, a Google Trends search of the term “cancer” was first performed (between October 1-10, 2015). Related search terms were recorded, with phrases specific to a subtype of cancer (“breast cancer”) excluded from this review. Depersonalized Google searches (using the United States domain) were then performed using each of these phrases, followed by evaluation of the first 20 results from each query. Comprehensive oncologic resources targeting patients were recorded, with sites focusing on a specific cancer subtype, nonscientific sites, and news articles excluded from further review. The remaining sites were evaluated for the presence or absence of information regarding 1) interventional oncology providers and 2) commonly performed imageguided interventional oncologic therapies. Results: Google Trends revealed three phrases commonly searched in relation with queries for “cancer”: “cancer diagnosis,” “cancer treatment,” and “cancer doctor.” Searches of all 4 terms revealed 22 distinct domains providing comprehensive cancer information of the total 80 evaluated search results. Of these 22 sites, 5 provided easily accessible patient information regarding IO/IR providers or therapies. In contrast, all 22 domains referenced providers or therapies related to 1) medical oncology and 2) radiation oncology, and 21 referenced surgical oncology. 9 sites discussed complementary/alternative medicine, 8 hematology, and 7 palliative/ancillary providers (nurses, social workers, etc.), and 4 diagnostic radiology. The most commonly referenced therapies on the 5 sites including IO in their cancer care resources were cryoablation, embolization (TACE/Y90), radiofrequency ablation, and HIFU. Conclusions: Although efforts to create the “interventional oncology” brand have been undertaken within the interventional radiology community, internet search queries using the most popular search engine in the United States in late 2015 demonstrate a significant lag in IR/IO’s presence on major web-based patient-centered oncologic resources. By late 2015, only 23% of major online cancer resources linked by Google in the United States discussed interventional oncologic therapies or providers in their online resources. Further efforts to quantify the effect of a strong online presence on IR/IO provider referrals and patient self-referrals should help to clarify the impact of this phenomenon, and may serve as a call to action for the interventional community to engage with administrators of these portals to bolster the IR/IO online presence. Poster 106: Irreversible Electroporation (IRE) of Local Advanced Pancreatic Adenocarcinoma: Long Term Follow-Up L. Tarantino2, V. Iovino3, G. Busto4, A. Nasto3, P. Gallo1, C. Accardo5, R. Giordano3. 1Campus Biomedico University, Rome, Italy; 2 Interventional Hepatology Unit, “A.Tortora” Oncology Hospital, Pagani, Pagani, Italy; 3“A.Tortora” Oncology Hospital, Pagani, Pagani, Italy; 4“A.Tortora” Oncology Hospital, Pagani, Pagani, Italy; 5 “A.Tortora” Oncology Hospital, Pagani, Pagani, Italy. Objective: Irreversible electroporation (IRE) is a non-thermal ablation technique for the management of locally advanced unresectable pancreatic adenocarcinoma (LAC). We present our first experience in a young patient with LAC successfully treated with IRE. Methods: After the exclusion of surgical resection of pancreatic mass, we offered the patient IRE as alternative treatment. After obtained informed consient, the patient was treated in open laparotomy under general anesthesia with IRE. Six insertions of multiple electrodes (up to 4 per insertion) were performed. Results: Case report: Female 24 years old. At admission she complained epigastric pain, nausea, lack of appetite and weight loss, absence of peritonism. Blood tests showed slight anemia (Hgb = 10.8%), hyperamilasemia (256 U/L) and mild increase of Ca-19-9 (65 U/ml). Virological tests and tumor markers were normal. Abdominal Ultrasound (US) showed a solid mass (diam.= 65 x 55 x 50 mm) involving the pancreatic body and isthmus. CT and MR showed complete thrombosis of the middle and distal portions of splenic vein and infiltration of the mesenteric vein wall. Color-doppler showed moderate/severe stenosis of terminal portion of superior mesenteric vein. Contrast enhanced US (CEUS) showed an hypovascular tumor thrombus in the splenic vein. Imaging did not show any lymphnode or distant metastasis. Surgical resection was excluded from the surgical team. The patient underwent US guided biopsy that showed pancreatic “Solid Papillary Adenocarcinoma”. We offered the patient IRE as alternative treatment. After obtained informed consient, the patient

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was treated in open laparotomy under general anesthesia with IRE. Six insertions of multiple electrodes (up to 4 per insertion) were performed. Intraoperative post treatment biopsy of the mass showed “signs of spotty necrosis and diffuse apoptosis”. The patient had an uneventful recovery and left the Hospital 5 days after treatment. 1 month post-treatment the patients was asymptomatic and evaluation by CT and MR showed “shrinkage of the tumor, partial bland thrombosis of the splenic vein, patent mesenteric and portal vein, small splenic infarction”. Two months post-treatment evaluation by PET/enhanced MR showed absence of pathological uptake and apparently absence of residual tumor or recurrence. At 26 months after treatment, 6 – 12 – 18 – 24 months CT follow-up, and bimonthly CDUS, showed complete regression of the mass, patent splenic/mesenteric veins and absence of local recurrence or distant metastasis. The patient is completely asymptomatic. Conclusions: In cases with poor indications for surgical resection, IRE seems to be a safe and highly effective alternative treatment for advanced stage pancreatic Solid Papillary Adenocarcinoma, even in presence of extensive thrombosis of spleno-portal-mesenteric veins. Poster 107: Percutaneous Electroporation Ablation of Pancreatic Adenocarcinoma L. Niu. Guangzhou FuDa Cancer Hospital, Guang zhou, China. Objective: To examine the safety and short-term efficacy of Percutaneous irreversible electroporation (IRE) ablation in unresectable pancreatic cancer. Methods: We carried out a prospective analysis of the adverse effects of Percutaneous IRE on patients with unresectable pancreatic adenocarcinoma, and evaluated the objective curative effect at postoperative day 30 r 7 using the modified RECIST criteria. Results: The 12 patients under study all successfully received IRE treatment. Some patients experienced adverse reactions within 30 days of the operation, including pain at the puncture site (5 patients, 41.7%), nausea and vomiting (3 patients, 25%), cough, postoperative hypoglycemia, hypokalemia, stomach and duodenal edema (2 patients, 16.7%), and gastric retention, fever, chest tightness and shortness of breath (1 patient 8.3%). After symptomatic treatment, these adverse effects were diminished, and severe complications related to IRE treatment, such as massive hemorrhage, bile leakage and pancreatic leakage did not occur. The serum amylase levels at 24 h and 7 d after IRE ablation were not significantly changed compared to those before ablation (P > 0.05). At 30 r 7 days after ablation, the curative effect was evaluated: one patient achieved a complete response (CR), 9 patients achieved a partial response (PR) and 2 patients exhibited stable disease (SD). Therefore, the tumor remission rate (percentage showing complete or partial response) was 83.3%. Conclusions: IRE was found to have advantages for treatment of pancreatic cancer: mild adverse reactions, high safety and short-term efficacy; however, its long-term effects require further study. Poster 108: A Call to Action for Medical Student Mentoring by Young Interventional Radiologists J.C. Hoffmann1, A. Eweka1, R. Chopra1, N. Azimov1, J. Flug2. 1Radiology, Winthrop-University Hospital, Mineola, NY; 2Radiology, University of Colorado School of Medicine, Aurora, CO. Objective: Early career interventional radiologists (IRs) are in a unique position to connect with medical students and can have substantial impact on recruiting the brightest medical students into radiology. This exhibit reviews why young IRs are vital to the recruitment and mentoring process, and provides multiple simple ways to advocate for IR and share this passion with medical students. Methods: With the implementation of the IR residency, medical students will need to determine whether to pursue a career in IR by the end of their third year of medical school. However, most medical students currently have little or no exposure to IR during the first few years of medical school. Recent survey data (not yet published) has demonstrated that 17% of current and recent IR fellows chose IR as a career by the end of their third year of medical school. Thus, substantial curricula changes and mentoring initiatives are needed to ensure that medical students get adequate exposure to IR so that they can make an appropriate career choice. Young IRs are in a unique position to connect with medical students, and there are many simple ways to respond to this call to action. Results: Young IRs are experienced enough to be excellent resources for medical students, yet at the same time are junior enough to understand the current medical school milieu. In addition, learners may feel more comfortable seeking career guidance from younger attendings, as they are closer in age and more recently completed training. This exhibit details ways for young IRs to mentor, educate, and inspire medical students. This includes becoming involved or helping to start an IR interest group, be a leader in medical student education at your institution, enlist medical students in research projects, expose medical students to life as academic and/or private practice IR, encourage medical students to join IR societies and attend national meetings, and share successes and failures in such endeavors with your colleagues.

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Conclusions: As early medical student exposure to IR becomes more important with the implementation of the IR residency, young IR physicians can play a critical role in cultivating IR interest among medical students. Poster 109: Evaluating Current and Recent Fellow’s Perception on the Interventional Radiology Residency: Results of a 2015 Survey J.C. Hoffmann1, A. Griffith1, A. Singh1, N. Azimov1, J. Flug2, M. Watts3, P. Rochon2. 1Radiology, Winthrop-University Hospital, Mineola, NY; 2 Radiology, University of Colorado School of Medicine, Aurora, CO; 3 Radiology, Philadelphia VA Medical Center, Philadelphia, PA.

Poster 110: Safety and Efficacy of Percutaneous Juxta-Cortical Cryoablation of Osteoid Osteomas D. Yim1, J.D. Prologo2, E. Lopez2, M. Hawkins2, K. Kim3, M. Whitmore2, C. Georgiades1. 1Interventional Radiology, Johns Hopkins University, Baltimore, MD; 2Radiology, Emory University, Atlanta, GA; 3 Interventional Radiology, Yale University, New Haven, CT. Objective: To establish the safety and efficacy of image-guided cryoablation of osteoid osteomas using juxta-cortical probe placement. This would obviate the need for general anesthesia during treatment. Methods: This was a retrospective study approved by the IRB. All patients who underwent percutaneous image-guided cryoablation at our institution using juxta-cortical probe placement for treatment of osteoid osteomas were identified (n=8). An intent-to-treat analysis was performed. Procedures were reviewed for probe placement, ablation protocol and complications. Patients charts were reviewed for demographics and relevant clinical history. Efficacy was determined with clinic visit, telephone and email follow up. Outcomes, including change in analgesic requirement, pain scores (utilizing the clinically implemented visual analog scale) and need for subsequent treatment was recorded. Results: Median follow-up was 12 months. Technical success was 100%. Seven patients (88%) had immediate and significant relief. One patient had no relief and the procedure was repeated with complete pain relief, yielding a secondary efficacy of 100%. Mean/median pre-procedure visual analog pain score was 9.2/9.8, compared to 1.9/0 on post-procedure follow-up (p<0.0078). Two minor complications were recorded including a transient sensory deficit and a skin blister that resolved spontaneously. Conclusions: Juxta-cortical cryoablation for osteoid osteomas is safe and has an efficacy (88% primary, 100% secondary) similar to the traditional intra-osseous approach. Confirmation of these results will obviate the need for general anesthesia during treatment.

Poster 111: The Metastatic Spine Disease Multidisciplinary Working Group Algorithms A.N. Wallace1, C.G. Robinson4, J. Meyer5, N.D. Tran3, A. Gangi6, M. Callstrom2, S.T. Chao7, B.A. Van Tine8, J.M. Morris2, B.M. Bruel9, J. Long10, R.D. Timmerman12, J. Buchowski11, J.W. Jennings10. 1 Neuroradiology, Mallinckrodt Institute of Radiology, Creve Coeur, MO; 2 Radiology, Mayo, Rochester, MN; 3Departments of Neurosurgery and Orthopedics, Neurooncology Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL; 4Radiation Oncology, Washington University, Saint Louis, MO; 5Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX; 6Interventional Radiology, University of Strasbourg School of Medicine, Strasbourg, France; 7 Radiation Oncology, Cleveland Clinic, Cleveland, OH; 8Internal Medicine, Washington University, Saint Louis, MO; 9Anesthesiology & Pain Medicine, MD Anderson Cancer Center, Houston, TX; 10 Mallinckrodt Institute of Radiology, Saint Louis, MO; 11Orthopaedic Surgery, Washington University, Saint Louis, MO; 12Radiation Oncology, University of Texas Southwestern, Dallas, TX. Objective: Management of metastatic spine disease requires multidisciplinary input. Treatment options not only include continually evolving medical therapy regimens, surgical techniques, and radiation technologies, but also emerging minimally invasive interventions. Among these is percutaneous tumor ablation, in which spinal tumors are accessed under imaging guidance and heated to cytotoxic temperatures to induce tumor necrosis. The Metastatic Spine Disease Multidisciplinary Working Group has developed straightforward recommendations regarding the use of available treatment strategies, including percutaneous tumor ablation. Methods: The Multidisciplinary Metastatic Spine Disease Working Group was composed of recognized experts in the fields of medical and radiation oncology, surgery, and interventional radiology from multiple Comprehensive Cancer Centers. The group convened to develop algorithms for the management of metastatic spine disease that incorporate patient prognostic factors and define the roles of emerging therapies, including percutaneous tumor ablation. The final algorithms were based on best available evidence, and when necessary, supplemented with expert opinion. Each recommendation in the algorithm was graded according to the Oxford Center for Evidence-based Medicine levels of evidence. Results: The Metastatic Spine Disease Multidisciplinary Working Group algorithms are presented in Figure 1. Conclusions: The Metastatic Spine Disease Multidisciplinary Working Group algorithms provide an evidence- and expert opinion-based framework for managing patients with spinal metastases and facilitating appropriate interdisciplinary referrals. These algorithms add to existing treatment guidelines by incorporating indications for emerging therapies, including percutaneous tumor ablation.

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Objective: To evaluate current and recent interventional radiology (IR) fellows’ perceptions on the planned IR residency. Methods: An anonymous, web-based survey was distributed to current and recent IR fellows across the United States. The survey contained 15 questions, most of which were based on a five-point Likert scale, while others contained free text responses. The survey was open for a three-week period in September 2015. The results were analyzed by two trainees and three interventional radiology attending physicians. Results: Sixty-four current or former IR fellows completed the survey. When asked at what point in their training did they decide to pursue a career in IR, 17% of respondents made this decision by the end of their third year of medical school. When asked if the IR residency will be an improved training pathway for interventional radiologists, 24% strongly agreed, 38% agreed, 20% were neutral, 8% disagreed, and 10% strongly disagreed. Based on current medical school curricula, 6% agreed that IR residency applicants will be ready to select such a pathway by the end of their third year of medical school, while 20% were neutral, 44% disagreed, and 30% strongly disagreed. When asked if sub-specialty IR fellowships with an emphasis on topics such as peripheral vascular disease, neuro-interventions, oncology, and/or pediatrics should be developed in the future, 15% strongly agreed, 36% agreed, 25% were neutral, 19% disagreed, and 5% strongly disagreed. Conclusions: A majority of current and recent IR fellows surveyed believe that the IR residency will be an improved training pathway for interventional radiologists. However, most of them chose a career in IR during their final year of medical school or during residency, and most believe that current medical school curriculum do not prepare medical students to decide upon a career in IR by the end of their third year of medical school. Thus, substantial immediate and longer-term curriculum changes are necessary to ensure that medical students know enough about IR to make an appropriate career decision by the end of their third year of medical school.

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Poster 113: US RESIN Registry for the Study and Evaluation of Patients Treated With SIR-Spheres

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A. Lipnik, F. Banovac, R.A. Omary, D. Brown. Vanderbilt University, Nashville, TN.

Metastatic Spine Disease Multidisciplinary Working Group algorithms for managing asymptomatic spinal metastases (A), uncomplicated painful spinal metastases (B), spinal metastases complicated by stable (C) and unstable (D) fractures, and MESCC (E). Treatment strategies are listed in descending order of recommendation. The letter in parentheses after each therapy denotes the grade of that therapeutic recommendation according to the Oxford Center for Evidence-based Medicine Levels of Evidence grading system. Abbreviations: cEBRT, conventional external beam radiation therapy; LE, life expectancy; mo, months; PS, performance status; SBRT, stereotactic body radiation therapy; VA, vertebral augmentation. Poster 112: Superselective Transarterial Conventional Chemoembolization in the Management of Unresectable Intrahepatic Cholangiocarcinoma I. Dedes, A. Drevelegas. Interventional Radiology Department, Interbalkan European Medical Center, Thessaloniki, Greece. Objective: The role of superselective transarterial conventional chemoembolization (cTACE) has yet to be clearly defined in patients with unresectable intrahepatic cholangiocarcinoma (ICC). The aim of this retrospective single-center study was to evaluate the effectiveness of cTACE in patients with unresectable ICC and whether this minimally invasive procedure could make patients candidates for hepatectomy and/or ablation. Methods: From 2002 to 2015, 42 patients (26 men and 16 women) with unresectable ICC were treated with superselective cTACE. Mean age was 64.7 years. Nineteen patients were Child-Pugh Class A and 23 were Class B. Hypervascular tumor presented in 32 out of 42 patients. Fifteen patients had solid tumor, 21 patients had multifocal while 6 patients had 2-5 lesions. Bilobar disease occurred in 73.8% of patients. The total number of cTACE performed was 125 and the mean cTACE sessions per patient was approximately 3 (range 1-14). The chemotherapeutics used were Mitomycin C and Cisplatin mixed with lipiodol. The embolization agent (microspheres) size ranged from 100-400 P. Local tumor response was evaluated by CT or MRI performed one month after cTACE, according to RECIST criteria. Six percutaneous biliary drainage and 9 percutaneous biliary angioplasty sessions were performed in 10 patients total to treat biliary obstruction. Results: No major complications occurred. After initial cTACE, 7 out of 42 (16.7%) patients showed a partial response, 19 patients (45.2%) showed stable disease whereas 16 patients (38.1%) showed progressive disease. One-year overall survival rate was 42.8%, 2-year was 21.4%, 3-year was 11.9%. Mean overall survival was 15.9 months. Four patients (9.5%) underwent hepatectomy after cTACE, while one patient underwent ablation. Mean survival for patients who underwent hepatectomy or ablation after cTACE was 32.5 months. Conclusions: Superselective transarterial conventional chemoembolization still has a role in unresectable ICC treatment. It is a safe and effective method and may provide prolonged survival. Also, in some cases it can help patients become candidates for hepatectomy and/or ablation.

Objective: Yttrium 90 (Y90) Resin microspheres are approved for use in the United States for treatment of colorectal cancer. They are frequently used off label for other liver dominant tumors. However, robust datasets regarding benefits and risks of this therapeutic modality across tumor types are lacking. Methods: The Radiation Emitting SIR-Spheres in Nonresectable (RESIN) national, multicenter registry will enroll patients with primary or secondary liver cancer scheduled for treatment with Y90 resin microspheres as part of their treatment. Patients may or may not receive concomitant systemic therapy as part of their overall oncologic management. This patient data is collected as a registry study and not as research on the experimental use of microspheres. Baseline data such as previous chemotherapy, performance status, tumor markers and receptor targets for biologic therapy will be tracked. Tumor response and concomitant therapy will be tracked, as will toxicities using the common terminology criteria for adverse events v4. An initial 8 centers are involved with a baseline goal to enroll over 350 patients/year. There are separate goals for patients with tumors that are more vs. less commonly treated with Y90. For patients with colorectal or neuroendocrine tumors, we hope to perform subgroup analysis to identify utilization strategies for personalized Y90 applications including trials focused on combinations with targeted therapies. For less commonly described treatment applications, we hope the registry data can plan future trials for less evaluated tumor types including breast, cholangiocarcinoma and others. Results: . Conclusions: Information generated from this national multicenter registry study will contribute to the oncology community’s understanding of US treatment patterns with Y90 therapy, gain additional insights into long-term outcomes and guide future research with Y90 therapy, especially for conditions with limited data. Poster 114: The Interventional Treatment of Gestational Trophoblastic Tumor J. Zhang, X. Han. Department of radiology intervention, the first affiliated hospital, Zhengzhou University, Zhengzhou, China. Objective: Most patients of gestational trophoblastic tumor can be completely healed through chemotherapy. However, drug resistance or recurrence may appear in 20% of the high risk cases, and these would lead to death for those patients. A more effective and less injury method is needed to solve these tough problems. The objective was to evaluate the value of interventional treatment for the patients with drug resistance or recurrence. Methods: Eighteen patients with gestational trophoblastic tumor were recruited into the study. All of them were given EMA-CO (VP-16,Act-D,MTX,CF,VCR,CTX) chemotherapy project three course of treatment and presented drug resistance or recurrence. The blood flow of nidus in the uterus was very rich. The serum levels of E-HCG declined slowly after three times chemotherapy. The interventional treatment was performed to these patients. Chemotherapeutics (PVB- DDP,VCR,BLM) was perfused through uterine arteries and ovarian arteries, meanwhile uterine arteries and ovarian arteries were embolized using gelatin sponge particle. After three weeks the second interventional treatment was given. The variation of serum levels of E-HCG and the diameter of nidus were observed after two times interventional therapy. Results: The operations of chemotherapy perfusion and embolism through uterine arteries and ovarian arteries were successful for all patients, and tumor dye was obvious through internal iliac artery or aortaventralis radiography. 14 patients were performed chemotherapy infusion and embolism through bilateral uterine arteries, and 4 patients were performed chemotherapy infusion and embolism through bilateral uterine arteries and unilateral ovarian arteries. The serum levels of E-HCG and the tumor diameter were measured after interventional therapy 18 days. We observed the varied serum levels of E-HCG and the tumor diameter before and after two times interventional therapy. The serum levels of E-HCG declined from 9208r716 mIU/L to 31.68r6.84 mIU/L, including 17cases was normal (0~35 mIU/L). The tumor diameter shrinked from 1.96r3.84cm to 0.82r0.32cm, including the nidus were disappeared in 12 cases. The difference of the levels of E-HCG and the tumor diameter were significant in the patients before and after two times interventional therapy. Conclusions: Interventional therapy was an effective method to treat gestational trophoblastic tumor of drug resistance or recurrence, and it was worth to spread.

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5.4% between the two years, but there was no statistical significance in this difference (p=0.47). TACE was the predominant procedure, representing 89.9% of the total in 2009 and 81.0% in 2013. TACE decreased by 14.8% between 2009 and 2013, but again this change was not significant (p=0.42). TACE MS ranged from 4.88-33.3% in 2009 and 4.66-21.4% in 2013 (p=0.41). Other procedures were less commonly performed with MS <3%. Conclusions: The number of IO procedures did not increase between 2009 and 2013 in a 5% Medicare LDS survey. Although the random sampling of the LDS may create an under-representative sample of IO procedures, growth has certainly not been robust. TACE remains by far the most commonly performed vascular procedure. Many procedures have less than a 1% MS, representing major growth opportunities and potential target areas for interventional oncologists treating patients in the Medicare demographic.

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Table 1. Procedure count and market share, 2009 and 2013 Poster 116: 885 Yttrium-90 Radioembolization Deliveries: Incidence and Role of Multiple Deliveries During Single Procedures J. Olsen1, M. Savin1, J. Campbell1, J. Savin2, C.O. Wong1. 1Beaumont Health, Royal Oak, MI; 2Florida International University Herbert Wertheim College of Medicine, Miami, FL. Objective: To evaluate the incidence, indications, and potential benefits of multiple Y90 deliveries during single radioembolization procedures. Methods: A retrospective review was conducted of 885 consecutive radioembolization deliveries during 820 procedures in 503 patients (mean age, 65 y; 293 male) performed between June 2001 and July 2013 at a single academic tertiary care hospital. The indication and benefit of each multiple delivery was determined. Results: Of 820 Y90 microsphere procedures, 757 (92.3%) were single deliveries, 61 (7.4%) were double deliveries, and two (0.2%) were triple deliveries. Multiple deliveries were used to avoid additional Y90 procedures and treatment delays in a variety of arterial variants and tumor locations. Arterial variants included middle hepatic arteries, accessory hepatic arteries, and unoccludable extrahepatic arteries arising from intrahepatic artery branches. Multiple deliveries were also used for large resin microsphere activities. (JVIR. 2015; 26:1769 - 1776) Conclusions: Multiple deliveries were helpful to reduce the number of procedures required to complete treatment, to avoid treatment dealys, to reduce the risk of GI tract embolization, and to allow for reliable delivery of high resin microsphere activities. Poster 117: Safety and Efficacy of Direct Puncture Tumor Embolization in Pre-Operative Patients with Juvenile Nasopharyngeal Angiofibromas (JNA) R.S. Chivate2, S. Kulkarni2, N. Shetty2, A. Polnaya2, K. Gala2, V. Bakare2, P.G. PATEL1. 1Interventional Radiology, Tata Memorial Hospital, Mumbai, India; 2Interventional Radiology, Tata Memorial Hospital, Thane, India. Poster 115: Changes in Interventional Oncology Volumes from 2009-2013 Using Medicare Data M. Koran1, R.A. Omary4, A. Lipnik3, F. Banovac5, D. Brown2. 1Vanderbilt University, Nashville, TN; 2Radiology, Vanderbilt University, Nashville, TN; 3Vanderbilt University, Nashville, TN; 4Vanderbilt University, Nashville, TN; 5Vanderbilt University, Nashville, TN. Objective: Interventional Oncology (IO) practice is a known area of interest within Interventional Radiology (IR). We hypothesized that IO procedures have increased over time in the Medicare population between 2009 and 2013. Methods: We accessed the Medicare Limited Data Set (LDS) representing 5% of the Medicare population in 2009 and 2013. We evaluated patients with liver tumors including primary (LIV), metastatic (MET), and neuroendocrine (NET) treated with chemoembolization (TACE), radioembolization (Y90), mapping for Y90 (MAA), and portal vein embolization (PVE). We cross-referenced the CPT codes of these procedures with relevant ICD-9 codes to determine patient/procedure number. We calculated changes and paired t-tests across the two years for each procedure and the percent of patients with each ICD-9 code treated [market share (MS)]. Results: The LDS included 2.4 million patients in 2009 and 2.8 million in 2013. Procedure volume and market share (MS) are in Table 1, and represent 5% of the Medicare patient sample. Overall, there were no statistically significant changes in volume or MS overall or by ICD-9. The total number of IO procedures decreased by

Objective: To study the role of direct puncture embolisation of juvenile nasopharyngeal angiofibromas, with emphasis on technique and possible complications. We also enlist extra precautions required during this procedure. Methods: Pre-procedure MRI with angiography was done along with CT angiography. Based on imaging findings tumour was gradded according to Fisch classification. In patients with JNA, direct puncture of tumour embolisation using either N-butyl cyanoacrylate (glue), ethylene vinyl alcohol copolymer (ONYX) or SQUID was done. Eleven cases have been done in age group of 12-16 yrs. Cerebral angiography to depict supply of tumour from external carotid (ECA) or internal carotid (ICA) or both which was followed by balloon occlusion test to check for contralateral circulation prior to embolisation. Transarterial embolisation from branches of external carotid artery using polyvinyl alcohol particles (PVA) was done. Direct puncture embolisation was done in cases supplied by ICA using CT scan and fluoroscopy for guidance and needle placement. Embolisation was performed till no tumoural blush was seen. Surgical excision of tumour was done within 24 hours of embolisation. Results: All patients tolerated procedure well with no neurological or cognitive deficits. Significant reduction in intra- operative blood loss achieved. There was easier and in toto resection of tumour which added to benefit of pre operative embolisation. Conclusions: Based on our results, pre surgical direct percutaneous embolisation of juvenile angiofibroma before surgical resection is safe and feasible.

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JNA as per Fisch grading wih supply from internal and external carotid arteries and efffect post embolisation

All Patients had undergone BTO and Trans-arterial Embolization for ECA supply ECA- External carotid artery, ICA- Internal Carotid Artery, DPTE- Direct Puncture Tumoral Embolization, EA-Embolizing agent

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Center, Memorial Sloan Kettering Cancer Center, Medical College of Wisconsin, and Stanford University Medical Center). The readability of these forms was then analyzed using the Oleander Readability software. The software reports the readability of a consent form in grade level form, using multiple scales that analyze variables such as sentence length and word complexity. Results: The 38 analyzed consent forms had a level of readability ranging from 7.5th to the 19th grade level. The mean readability score of all the PEMs included in our study was the 12.4th grade level, with a standard deviation of 2.8. The mean readability of the pediatric consent forms was the 10.4th grade level, with a standard deviation of 1.3. The mean readability of the non-pediatric specific consent forms was the 14.4th grade level with a standard deviation of 2.5. A two-tailed t-test revealed a statistically significant difference in readability between consent forms written for pediatric patients vs. non-pediatric patients (p< 0.01). Conclusions: Although the pediatric consent forms were written at lower grade level than the non pediatric consent forms, all 38 patient consent forms included in this study were written above the 7th grade level, with some as high the 19th grade level. This is clearly above the recommendation of the American Medical Association and National Institutes of Health that patient education materials be written at the 3rd to 7th grade reading level. It is therefore likely that although our patients readily sign consent forms, they may not fully understand the risks and benefits of the procedure they are to undergo. Poster 119: Percutaneous Vertebral Augmentation for Malignant Lesions in the Thoracic Spine: An 18-Month Follow-Up on Pain Reduction and Mobility Improvement D. Filippiadis1, L. Reppas1, S. Grigoriadis1, C. Batistaki2, E. Brountzos1, N. Kelekis1, A. Kelekis1. 12nd Department of Radiology Department, University General Hospital “Attikon”, Athens, Greece; 2Anesthesiology Department, University General Hospital “Attikon”, Athens, Greece.

Carotid agiography pre and post embolization with PVA particles through ECA branches with direct puncture through intra nasal route, onyx used as embolizing agent. Poster 118: Are Patient Consent Forms Too Complex To Understand? Readability Analysis of Interventional Radiology Consent Forms T. Ramchand1, S. Patel1, H.S. Kim2. 1Radiology, Yale New Haven Hospital, New Haven, CT; 2Radiology, Yale New Haven Hospital, New Haven, CT. Objective: The purpose of this study is to analyze the readability (in grade level) of the informed consent forms provided to patients prior to Interventional Radiology Procedures. Consent forms are used as tools to educate our patients regarding the nature of their procedure, the risk involved, and the potential benefits. Obtaining informed consent before therapeutic procedures has become not only an ethical standard, but also a legal one. However, countless prior studies have shown that patient education materials are written at a higher than recommended reading level. Therefore, it is the aim of our study to analyze the readability of the informed consent forms used in interventional radiology. Methods: Interventional Radiology departments were contacted directly via email, and asked to respond with a blank patient informed consent form attached. Some programs used one form for all procedures, while others had dedicated forms for each separate procedure. In total, 38 consent forms were obtained for review, from 5 separate institutions (Boston Children’s Hospital, Johns Hopkins University Medical

Objective: The purpose of our study is to assess clinical outcome (on terms of pain reduction and mobility improvement) and safety (potential complications and implant migration) of patients with symptomatic malignant lesions in the thoracic spine treated by percutaneous vertebral augmentation with biocompatible polymer (KIVA implant). Methods: During the last 2 years, 10 patients with symptomatic malignant lesions in the thoracic spine underwent percutaneous augmented vertebroplasty [a biocompatible polymer was introduced within the vertebral body and filled with PMMA]. Under fluoroscopic guidance and unilateral, transpedicular approach, a working cannula and coaxially the KIVA system were introduced in the vertebral body of interest. Initially a coil was advanced to create a path through the cancellous bone guiding the KIVA Implant which deploys as a stacked, cylindrical column centered at vertebral body’s midline. Cone beam CT was performed immediately after percutaneous vertebroplasty augmented with the KIVA implant. Standard x rays and Computed Tomography scans were performed during follow-up. Pain prior, the morning after and at the last follow-up (average follow-up 12 months) were compared by means of a numeric visual scale (NVS) questionnaire. Cement extravasation and implant migration were also recorded. Results: Comparing the pain scores of questionnaires prior (mean value 8.9 NVS units) and post (mean value 1.5 NVS units) treatment, there was a mean decrease of 7.4 NVS units on terms of pain reduction and life quality. Overall mobility improved in 10/10 (100%) patients. No complication was observed. No symptomatic or clinically significant extravasations occurred. No implant change or migration was observed during the 18 months follow-up period. Conclusions: Preliminary results in treatment of symptomatic extreme vertebral fractures and malignant lesions in the thoracic spine report significant pain reduction and mobility improvement with no proof of implant migration. Further studies however, are required. Poster 120: Adrenal and Ovarian Vein Sampling to Assess Source of Androgen Excess B.K. Achakzai1, R. Riaz2, C. Patel1, D. McVinnie1. 1Interventional Radiology, Henry Ford Hospital, Detroit, MI; 2Henry Ford Hospital, Detroit, MI. Objective: To demonstrate the utility of combined ovarian and adrenal vein sampling (COAVS) in localizing source of androgen excess. In females with virilization, androgen excess may be of adrenal or ovarian origin. Androgen producing ovarian tumors may be imaging occult and functional versus non-functional adrenal adenomas have identical appearance. COAVS can localize the androgen source in select patients. Methods: A 61 year old female presented with virilization and elevated serum total testosterone. CT abdomen showed a left adrenal adenoma. MRI pelvis showed atrophic ovaries. The patient was referred for COAVS. Venous sampling was performed during Cosyntropin infusion. Samples for testosterone, dehydroepiandrosterone sulfate (DHEAS), and cortisol were obtained from the adrenal veins and IVC, and samples for testosterone and DHEAS were obtained from the gonadal veins.

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Results: Despite dilution of the right adrenal sample (cortisol twice IVC when ideally it should be five times IVC), sampling was considered diagnostic of a right ovarian androgen source as there was no right adrenal nodule, testosterone to cortisol ratio for both adrenal veins was suppressed relative to IVC, and the right gonadal vein testosterone was markedly elevated (Table 1). The patient underwent bilateral oopherectomy. Pathology showed a 1.5 cm right ovarian Leydig cell tumor. Serum total testosterone normalized post operatively. Conclusions: In females with virilization, when imaging is not helpful, COAVS may definitively localize the source of androgen excess.

G. Carberry1, N. Rubert2, J. Vetter2, M. Woods1. 1Radiology, University of Wisconsin, Madison, WI; 2Medical Physics, University of Wisconsin, Madison, WI. Objective: To compare operator radiation exposure from abdominal fluoroscopy during transradial and transfemoral artery approaches. Methods: The center of the x-ray field on a Siemens Zeego angiographic unit was positioned over a medium (30x30x20cm) and then a large (30x30x30cm) fluoroscopy phantom. The field size, table height and SID were held constant at 48 cm, 15 cm and 105 cm, respectively. Two ion chambers located 0.6 m and 0.9 m from the floor were positioned at 3 locations from the center of the x-ray field: a) adjacent to an abducted arm board b) adjacent to the proximal right inguinal region to replicate the position of the operator during use of a base catheter, and c) adjacent to the distal right inguinal region to replicate operator use of a longer microcatheter system. Three levels of radiation shielding between the phantom and ion chambers were used at each dosimeter position. The radiation exposure rate was measured with Fluoro Angio Mode at 10 f/s from the PA, RAO and LAO tube orientations for each level of shielding. The distance between operator positions to center of the x-ray field was measured. The mean of the exposure rates over the three tube positions and two ion chamber heights was calculated for each level of shielding for both phantoms and for the three dosimeter positions. Results: The distance from the center of the x-ray field to the operator positions for the transradial approach (TR), transfemoral approach with a base catheter (TFb) and with a microcatheter system (TFm) were 102 cm, 79 cm and 110 cm, respectively. The mean exposure rates without shielding for the medium phantom at the TR, TFb and TFm positions were 1.86 uGy/hr (+/- 0.65), 2.87 (1.12) and 1.21 (0.35), respectively. The values rose in proportion for the large phantom. Average reduction in exposure with the use of minimal radiation shielding from the TR, TFb and TFm positions was 58.2% (+/- 8.41), 62.9 (2.76) and 49.8 (0.78), respectively; whereas average reduction with the use of maximum shielding was 98.7% (+/- 0.07), 99.1 (0.07) and 97.1 (0.56), respectively. Conclusions: The transradial position with the patient’s arm abducted resulted in a lower operator radiation exposure compared to the transfemoral position with use of a base catheter but a slightly higher rate than at the transfemoral position with use of a microcatheter. Operator radiation exposure may be reduced with abduction of the patient’s arm after obtaining transradial access to facilitate use of radiation shielding and to increase operator distance from the x-ray source.

Poster 122: Cryoablation: A Technically Successful Treatment for a Rare Scapular Fossa Glomus Tumor C.A. Jaramillo1, J.J. Zechlinski1, D. Mendoza2, S. Tutton1. 1Medical College of Wisconsin, Milwaukee, WI; 2Pathology, Medical College of Wisconsin, Wauwatosa, WI. Objective: Glomus tumors are rare but potentially morbid perivascular neoplasms that comprise 1-2% of soft tissue tumors. Classically located in acral cutaneous tissues and treated surgically, deep lesions represent a small minority of glomus tumors. We report a recent percutaneous cryoablation of a scapular fossa glomus tumor in a 47 year old male organist presenting with ten years history of lancing right shoulder pain radiating down his arm, aggravated by shoulder adduction and arm extension. We discuss relevant pathology, anatomy, and intra-operative considerations. Methods: The complicated anatomy of the shoulder girdle makes resection a technically difficult surgery with considerable morbidity and a protracted recovery. After multidisciplinary discussion, we elected for a minimally invasive debulking procedure for local tumor control and symptomatic relief. MRI revealed a 4.5 x 3.5 cm T2 hyperintense enhancing mass with the subscapularis muscle abutting the anterior scapula, as well as regional adenopathy near the suprascapular notch. CT-guided biopsy demonstrated a deep soft tissue glomus tumor. Percutaneous cryoablation was performed under monitored anesthesia care and CT guidance using a posterior trans-scapular approach. A large zone of ablation was created with overlapping freeze-thaw-freeze cycles along the long axis of the lesion using a single 24 mm probe. Post-procedure CT demonstrated good coverage, and no immediate neurologic deficits were observed on clinical exam. Results: Immediate, near-complete resolution of pain was observed shortly after the procedure. The patient was discharged following an uneventful overnight recovery and observation. Follow-up visit at 2 weeks indicated sustained pain relief, strength, and range of motion, although arm abduction remained partly limited. MRI follow-up is planned at 6 months. Though generally benign, a review of the literature suggests that glomus tumors have an increased malignant potential with larger size, depth, and atypical mitotic figures. Often involving neural tissue and frequently misdiagnosed, pain and multiple ineffective treatments make these rare neoplasms an important subject to address. Conclusions: Percutaneous cryoablation is a safe and an increasingly accepted modality for the treatment of soft tissue neoplasms. Its use in the treatment of glomus tumors has not, to our knowledge, been previously described. The application of cryoablation was a technical success, sparing a highly morbid surgical resection and providing early, marked clinical improvement of pain and function.

MRI showing the 46.7x14.1mm scapular fossa lesion.

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Poster 121: Operator Radiation Exposure with Transradial vs. Transfemoral Arterial Access During Abdominal Intervention: A Simulation with an Angiographic Phantom

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of subcapsular hepatic tumors. Additionally, we discuss technical challenges and post-procedural implications for these situations through a case-based approach. Conclusions: Microwave ablation is an effective tool for the treatment of hepatic tumors, with building evidence that it is safe even in conditions previously considered dangerous or contraindicated. This work reviews this data, discusses technical considerations using a case-based approach, and reviews technical tips and tricks to ensure successful and safe ablation. Poster 125: Percutaneous Image-Guided Pancreatic Duct Interventions in the Management of the Cancer of the Head of the Pancreas

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M. Mizandari1, N. Habib2, T. Azrumelashvili3. 1Tbilisi State Medical University, Tbilisi, Georgia; 2Surgery and Oncology, Imperial College London, London, United Kingdom; 3Radiology, Tbilisi State Medical University, Tbilisi, Georgia.

Intraoperative CT shows cryoablation probe traversing right scapula from a posterior approach and a zone of ablation. Poster 123: Upregulation of Antioxidants in Thyroid Tumors: A Mechanism to Promote Tumor Survival and Growth G.G. Chen, S. Wang, A. Vlantis, C. van Hasselt, M. Tong. Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong. Objective: Thyroid grand is under the constant oxidative stress which is needed for the production of thyroid hormones. Pathologically, oxidative stress may contribute to the development and treatment of thyroid tumors. The aim of this study was to determine antioxidant levels in thyroid tumors and possible interference with anti-tumor treatments. Methods: Thyroid samples of both tumor and non-tumor tissues were obtained from 53 patients with benign or malignant thyroid tumors. The levels of manganese superoxide dismutase (MnSOD), thioredoxin reductase 2 (TXNRD2), glutathione (GSH), glutathione peroxidase (Gpx), catalase (CAT), and 27kd heat-shock protein (hsp27) were evaluated in both thyroid tissue samples and cultured thyroid cells by immunohistochemical staining and Western blot. Hydrogen peroxide (H2O2) was used to generate oxidant stress in cell culture experiments. Results: Our results showed that the levels of MnSOD, TXNRD2, GSH and Gpx were increased in both malignant and benign tumors, particularly the former. To verify the result of thyroid tissue study, we treated thyroid cells with H2O2 and the same patterns of antioxidant changes were observed. Hsp27 was also found to be upregulated after the H2O2 treatment. The expression of hsp27 in thyroid cancer, follicular adenoma, multinodular were upregulated 8.24 fold, 6.96 fold, 3.09 fold, respectively. The increase of antioxidants damped the sensitivity of tumor cells to chemotherapeutic agents. Conclusions: In conclusion, our study demonstrated that the levels of hsp27 together with MnSOD, TXNRD2, GSH and Gpx were significantly upregulated in thyroid tumor cells. The increase of these antioxidants is observed in both malignant and benign tumors, particularly the former. The findings suggest that the upregulation of antioxidants is likely a protective mechanism of tumor cells to maintain their survival and growth.(The study was supported by CUHK direct grants: 2013.1.011, and 2013.2.007).

Objective: Percutaneous image-guided pancreatic duct (PD) drainage and subsequent second- line procedures (duct recanalization and endoluminal biopsy) are presented Methods: Eighteen symptomatic pancreatic cancer patients (pancreatitis and/ or recently revealed hyperglycemia) underwent percutaneous US (8 cases) or CT (10 cases) guided drainage, using 22 to 18G needles. PD neck segment was accessed in 2 cases, body segment - in 11 and the tail segment - in 5 cases. Hydrodissection was used to create the safe needle route in 3 CT guidance cases. Transgastric and tranhepatic puncture route was used in 4 and 5 cases respectively. A fixed tip “Pig-Tail” drainage catheter was placed under the real-time fluoroscopy guidance. All second line procedures (metal stent placement - 2, endoluminal RFA & metal stent placement - 7, endoluminal biopsy- 2) were performed under fluoroscopy guidance using the PD drainage fistula. Endoluminal RFA was performed using a novel 5 Fr diameter RF device, metal stent placement was achieved using a conventional guidewire technique. Endoluminal biopsy was performed using a forceps device. After PD recanalization safety drainage catheters were repositioned and kept closed for a week prior to removal. Results: PD was drained in 18 cases; in post-biopsy pancreatic fistula case non-dilated PD was accessed. Clinical improvement was documented by the gradual reduction in clinical symptoms and improved blood test results, having 300 to 900 ml pancreatic fluid discharge per day. Four cases of diabetes recent onset showed a dramatic improvement in hyperglycemic control with complete cessation of medication in 2 cases and a significant dose reduction in 2 cases. Second-line procedures were fulfilled in 9 (90.0%) of 10 attempted cases. Endoluminal biopsy enabled to get tissue material; all patients tolerated the procedures well, there was no 30-day or hospital mortality. There were no observed technique specific complications, such as hemorrhage, duct of vessel perforation or infection. Conclusions: PD drainage, stenting, endoluminal RFA&stenting, endoluminal biopsy appear to be safe and effective; percutaneous drainage might be considered for symptomatic PD occlusion as an alternative of retrograde stent placement and EUS guided antegrade intervention, being the only possible option after previous GI tract surgery or retrograde access failure. PD recanalization and endoluminal biopsy should be routinely suggested as the possible options in the management of inoperable pancreatic cancer.

Poster 124: Is Hepatic Microwave Ablation Near Critical Structures Dangerous? A Case-Based Review A. Smolock2, M.M. Cristescu1, G. Carberry3, S.A. Wells2, T. Ziemlewicz2, M. Lubner2, J.L. Hinshaw2, C. Brace2, F. Lee2. 1University of Wisconsin, Madison, WI; 2Radiology, University of Wisconsin, Madison, WI; 3 University of Wisconsin--Madison, Madison, WI. Objective: To review and evaluate concerns over the safety of microwave ablation in locations traditionally viewed to be difficult or dangerous using an evidence-based approach. Methods: Microwave ablation is the most powerful form of thermal ablation due to its ability to rapidly generate temperatures greater than 100°C. Concerned over the potential for collateral damage, operators may be reluctant to ablate tumors adjacent to critical structures, such as the diaphragm, heart, bowel, bile ducts, hepatic and portal veins, and IVC. Additionally, some operators are hesitant to directly puncture tumors from fear of tumor seeding. Results: Our institutional experience with microwave ablation has demonstrated it to be not only efficacious but also remarkably safe when used next to critical structures. We summarize our published and investigational data regarding ablation adjacent to potentially susceptible structures, including the diaphragm, heart, bowel, bile ducts, hepatic and portal veins, and IVC. We also discuss our experience with direct puncture

Patient is in prone position; arrows identify the dilated PD

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Neutropenia toxicity parameters

puncture needle canula and conducted wire are seen in PD Poster 126: Modeling Chemotherapy Induced Neutropenia in Patients Undergoing Interventional Radiology Procedures A. Goel1, A. Covey2, L.A. Brody2, P. Robson2, J.P. Erinjeri2. 1Radiology, Columbia University Medical Center, New York, NY; 2Interventional Radiology Service, Memorial Sloan-Kettering Cancer Center, New York, NY. Objective: To model the risk of severe chemotherapy-induced neutropenia for the most frequently used chemotherapy agents in patients undergoing interventional radiology (IR) procedures. Methods: Between May 2010 and September 2014, 24,780 patients underwent 49303 IR procedures. During this period, these patients were administered 443,344 doses of chemotherapy. We compiled a list of the 24 most frequently administered chemotherapy agents (363,987 doses, 82%). Using the pharmacology literature, we determined percent severe neutropenia (grade-3 or grade-4), nadir time parameters, and the class of chemotherapy. Using these values, we created a Monte Carlo simulation to assess severe neutropenia in patients receiving these chemotherapy agents. Our simulation assumed a uniform distribution across nadir time parameters. We ran our simulation on 1 million patients and computed a probability distribution of events over time. We then ran our model with 10 million patients to verify convergence. Neutropenia risk for each drug was compared to all neutropenia causing drugs using Pearson’s chi-square test. Neutropenia events per week were individually, pairwise compared using a two-sided Student’s t test. Results: Our model predicted that 25% of patients (258,766) would experience a neutropenic event within 30 days of chemotherapy administration, with an average of 12,270 r 5,752 events per day. All events occurred between days 8-28. Events per week were as follows: week-1 zero (0% of events), week-2 85,632 (33.1% of events), week-3 114,741 (44.3% of events), and week-4 58,393 (22.6% of events). Neutropenia rates across all week-to-week comparisons were significantly different (all p<0.001). There were significantly more events experienced between days 9-27 (p<0.05). Greatest risk of neutropenia was on day 14 with 21,596 events (2.2% of all patients). Of the 12-neutropenia causing agents, Paclitaxel (22.8%), 5-Fluorouracil Leucovorin (19.3%), and Gemcitabine (16.5%) contributed the most events. Conclusions: Patients undergoing IR procedures are least likely to experience neutropenia during week-1 after administration, and have a significantly higher risk of events between days 9-27.

A Monte Carlo simulation that models severe neutropenia events over time. Poster 127: Sociodemographic Factors in the Outcomes of Intrahepatic Cholangiocarcinoma: A SEER Population Study A. Ghodadra1, M. Xing2, K. Kim2. 1Radiology, UPMC, Pittsburgh, PA; 2 Radiology, Yale, New Haven, CT. Objective: Intrahepatic cholangiocarcinoma is an increasing cause of primary hepatic cancer. In this study, we explored the relationship between sociodemographic factors and survival utilizing the Surveillance, Epidemiology, and End Results database. Methods: Data for all patients with the diagnosis of intrahepatic cholangiocarcinoma diagnosed from 2000 to 2011 was queried from the Surveillance, Epidemiology, and End Results database. Patients had at least three years of follow-up data and did not receive surgery or external radiation therapy. These patients likely received chemotherapy and/or locoregional therapy. The relationship between sociodemographic factors, including age, sex, race, regional normalized cost-of-living ratio, regional prevalence of poverty and tumor grade and overall survival was assessed using Cox proportional hazard modeling. Results: A total of 5,508 patients met criteria and had available data for sociodemographic factors. The average age in the patient population was 69.2 years (SD: 13.5) with 50.4% being male. A total of 79.4% of subjects were categorized as white, 7.6% black and 13.0% as other (American Indian, Asian/Pacific Islander). The median percent of people living below poverty in the regions patients lived was 7.8% (quartiles: 5.3, 12.7) and the median normalized cost-of-living ratio in these regions was 1.09 (quartiles: 0.92, 1.17). In this population, age, sex, race, normalized cost-of-living ratio, and regional prevalence of poverty were statistically significant correlates of overall survival (p < 0.005). A total of 1,792 patients had sociodemographic and tumor grade data available. Of these patients, 12.1% had Grade 1, 43.8% had Grade 2, 41.2% had Grade 3 and 2.9% had Grade 4. After correction for tumor grade, in this population, age, sex, normalized cost-of-living ratio and regional prevalence of poverty persisted as statistically significant correlates of overall survival (p < 0.05). Patients who lived in regions with a higher normalized cost-of-living ratio had increased overall survival (range risk ratio: 0.79 95% CI: 0.63 – 0.99, p = 0.041). Similarly, patients who lived in regions with a higher regional prevalence of poverty had lower overall survival (range risk ratio: 1.59, 95% CI: 1.05 – 2.41, p = 0.028). Risk ratios and confidence intervals are shown in Table 1. Conclusions: Higher sociodemographic status measured by regional normalized cost-of-living ratio and regional prevalence of poverty are significant correlates of overall survival in patients with intrahepatic cholangiocarcinoma treated with chemotherapy and/or locoregional therapy. Increased focus on addressing the impact of sociodemographic status is needed to improve overall outcomes in this population.

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Chemotherapy agents are in descending ordered by number of patients on each agent.

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Table 1. Results of Cox Proportional Hazard Modeling on Sociodemographic Data

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Poster 128: Benign Abdominal Tumors: Percutaneous Ablation Should be the First Line T. Ziemlewicz, J.L. Hinshaw, M. Lubner, S.A. Wells, M. Alexander, F. Lee. Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI. Objective: Benign tumors in the abdomen rarely require treatment, however occasionally intervention is warranted due to symptoms, risk of hemorrhage, or risk of malignant transformation. Surgery is the historical gold standard, although can be associated with significant morbidity and occasional mortality. Meanwhile, the majority of benign tumors that are indicated for surgical resection are amenable to percutaneous ablation, which confers a minimal risk of morbidity. Methods: Indications for ablation of benign tumors will be outlined and the current evidence will be reviewed. Approach to patient work-up and treatment considerations specific to benign tumors will be discussed. Practical tips for treating benign tumors will be demonstrated with numerous case examples. Results: We will discuss our clinical results treating benign tumors with a focus on hepatic hemangiomas, adenomas, and cysts as well as renal angiomyolipomas and oncocytomas. Conclusions: Percutaneous ablation is effective for treating benign tumors that would otherwise undergo surgery. Due to the decreased morbidity when compared with surgery, ablation should be the first line treatment for benign tumors requiring intervention. Poster 129: Splenic Volume Changes After Radioembolization with Ytrium-90 Resin Microspheres as A Marker for Treatment Response S. Baghai1, E. Shaaya1, A.Y. Kim2. 1Interventional Radiology, Georgetown University Hospital, Arlington, VA; 2Dept of Radiology, Medstar Georgetown University Hospital, Washington, DC. Objective: The purpose of this study was to assess potential correlation between splenic volume (SV) changes and treatment response after Y-90 radioembolization (Y-90 RE). Methods: Retrospective review of 99 patients that underwent RE over a 24 month period with Y-90 (single lobe, sequential bilobar, or whole liver) was performed. Patients with a CT, MRI, or PET/CT of the abdomen before and after treatment were included in the study. Patients without pre- and post-treatment imaging, poor quality imaging, and patients who were asplenic or had mixed responses (i.e., stable, complete, or partial local response with global progression of disease) were not included in the analysis (total excluded: 48). SV were calculated using the AquariusNet software on the most recent imaging prior to treatment and the most recent imaging available after treatment utilizing 1 or 3 mm slice images. Imaging suitable for SV calculation was determined if the entire spleen was imaged with the intention to compare SV on similar imaging modalities. The majority of patients had pre-treatment imaging within 2 months of Y-90 RE and post-treatment imaging ranging from 2 months to 2 years after treatment. Local response to treatment was assessed using the RECIST criteria, as determined on the most recent follow up imaging available. Global response was assessed using the patient’s most recent imaging studies. Results: Fifty-one patients (34 males and 17 females) were included in the analysis. Diagnoses included metastatic colorectal cancer (mCRC) (n=19), hepatocellular carcinoma (HCC) (n=13), metastatic pancreatic cancer (mPC) (n=8), cholangiocarcinoma (ChCa) (n=4), metastatic pancreatic neuroendocrine tumor (mPNT) (n=1), metastatic neuroendocrine tumor (mNT) (n=3), metastatic squamous cell carcinoma of the head/neck (mSCC) (n=1), metastatic duodenal adenocarcinoma (mDA) (n=1), and metastatic gastric cancer (mGCa) (n=1). Twenty-nine patients underwent sequential bilobar treatment and 22 underwent single lobe treatment only. Thirty-one patients had local and overall disease progression: 14 mCRC, 6 mPC, 5 HCC, 3 ChCa, 1 mDA, 1 mNT, and 1 mSCC. In this group, there was an average 23% increase in SV (average pre-RE SV: 342.6 cm3; average post-RE SV: 422.1 cm3; p=0.02; 95% CI of difference: 16.9<79.5<142.1). Twenty patients who had both local and global stable disease, complete response, and/or partial response, including 8 HCC, 5 mCRC, 2 mNT, 2 mPC, 1 mGCa, 1 ChCa, and 1 mPNT. There was an average 10% increase in SV (average pre-RE

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SV: 426.5 cm3; average post RE SV: 467.4 cm3; p=0.56; 95% CI of difference: -97.1<40.9<178.9). Of the 20 patients who had both local and global stable disease, complete response, and/or partial response, 14 had local stable disease, 6 had partial response, and 0 had complete response. In the 14 patients with local stable disease, there was an average 11% increase in SV (average pre-RE SV: 409.6 cm3; average post-RE SV: 453.8 cm3 ; p=0.26; 95% CI of difference: -175.3<-44.2<86.9). In the 6 patients with local partial response, there was an average 7% increase in SV (average pre-RE SV: 465.9cm3; average post-RE SV: 499.2 cm3; p=0.41; 95% CI of difference: -299.1<-33.3< 232.5). Conclusions: Statistically significant increases in splenic volume after Y-90 RE were noted in patients with disease progression but not in patients achieving disease control (i.e., partial response, complete response, or stable disease). This may be reflective of Y-90 particle distribution in tumor versus background liver for the two groups. Further studies are needed to validate our findings. Poster 130: Percutaneous CT and US Guided Cryoablation for Superficial Soft Tissue Tumors (SSTT): A Single Institution Experience L. Carmignani1, A. Pagliari1, M. Fedi2, M. Lupi1, L. Vannucchi1, M. Di Lieto3, S. Giannessi2, P. Pacini1. 1Radiology, St Jacopo Hospital, Pistoia, Italy; 2General Surgery, St Jacopo Hospital, Pistoia, Italy; 3 Clinical Oncology, St Jacopo Hospital, Pistoia, Italy. Objective: Superficial soft tissues are not uncommon sites of metastatic disease from breast carcinoma, uterine sarcoma, melanoma and other types of cancer. In several cases surgery is not feasible and chemoterapy alone is unable to provide effective outcomes in terms of local control and survival rate. For these reasons, multidisciplinary protocols are increasingly recommended, in an attempt to prolong the disease – free interval and to ensure a good quality of life for this patients. We report our experience to assess the feasibility, safety and effectiveness of percutaneous cryoablation joined with chemotherapy for the treatment of primary and metastatic tumors located in superficial soft tissues such as breast, armpit. groin, abdominal wall and muscles of the extremities. Methods: From January 2012 to June 2015 we treated 23 patients (8 male, 15 female), with a median age of 65 years (52 – 85) and a total of 37 SSTT (1 cm – 9 cm in maximum diameter/1 – 7 lesions per patient). Lesions consisted of 14 breast carcinomas (9 local recurrences/5 contralateral metastases), 11 metastases from uterine sarcomas (5 abdominal wall, 1 groin and 5 muscular locations), 10 metastases from melanoma (7 armpit and 3 chest wall locations), 2 deltoid muscle metastases from scapular chondrosarcoma. Treatment plan consisted of perioperative chemotherapy and US or CT guided percutaneous cryoablation. For each patient at least one lesion was biopsied before treatment. All patients were studied with contrastographic CT which did not demonstrate any other location than those of superficial soft tissues. All procedures were discussed and endorsed in the Domestic Tumor Board and each patient gave written informed consent. Results: Cryoablation was successfully performed on all 23 outpatients using only local anesthesia. No major complications occurred; no procedure – related deaths. Follow – up was executed with contrastogtaphic CT or MRI examinations at 1, 3, 6, 9, 12 months after treatment and then on a yearly basis. The 1 month follow – up demonstrated total necrosis (referred as absence of contrast enhancement) in 32/37 SSTT (86,4%) and partial necrosis (referred as residual contrast enhancement) in 5/37 SSTT (11,6%). Lesions denoting partial necrosis after 1 month immediately underwent a second percutaneous cryoablation session with no evidence of disease at the subsequent 1 month CT/MRI examination. Due to the very superficial location of the lesion, slight skin damages occurred in 7 cases with complete scarring after about 1 month just with appropriate skin medications. Two patients with lesions located in the forearm muscles showed transient (15 - 20 days) limited mobility of the hand of the treated limb caused by stunning and subsequent peripheral nerve palsy. The median follow-up was 20,3 months (range 6-42 months). At the time of the last follow-up 4 patients are dead for disease progression, 12 patients has no evidence of disease, 7 are alive with disease. Conclusions: US and CT guided percutaneous cryoablation of superficial soft tissue malignant lesions demonstrates high success and low complication rate. Although the purpose is palliative, cryoablation is able to provide local control also for multiple soft tissue locations, without the need for general anesthesia or sedation, on an outpatient basis. Poster 131: Radiofrequency Ablation for Recurrent Fibromatosis: Long Term Outcome from Tata Memorial Center G.J. Mukunda, S. Kulkarni, N. Shetty, A. Polnaya. Interventional Radiology, Tata Memorial Hospital, Mumbai, India. Objective: To evaluate the safety and efficacy of RFA in managing recurrent fibromatosis. Methods: A retrospective analysis of 40 fibromatosis patients treated with 104 sessions of RFA from January 2008 to November 2015 was done. Inclusion criteria were

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Results: nsPEF reduced tumor volume compared to the control group (p<0.05), it also inhibit serum alkaline phosphatase and lung metastasis, prolonged the survival time without joint deformity or capsule rupture. nsPEF cannot eradicate the tumor as amputation surgery (p<0.05), but the complication and hospitalization time were lower. Conclusions: Local nsPEF ablation was found to be effective in achieving longer survival and less lung metastasis without chemotherapy, radiotherapy or biological therapy. As a non-thermal ablation method, nsPEF has potential to treat osteosarcoma as a palliative therapy for osteosarcoma patients who constricted for surgery.

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recurrent fibromatosis refractory to primary treatment, i.e. surgery, RT, CT or immunotherapy. RFA was done under CT guidance. Patients were followed up every 3 months to assess clinical benefits and radiological response. Response evaluation was done clinically by improvement in the range of movements (ROM) and radiologically by calculating change in volume of the lesion at follow-up and percentage decrease. Results: A total of 104 sessions of RFA was done in 40 patients with fibromatosis (mean number of sessions, 2.8). Mean follow-up was 34 months (range, 1-96 months). 9 patients had involvement of upper limb, 14 lower limb, 6 chest wall, 3 mediastinum, 2 mesentric, 6 retroperitoneum and pelvis. Quantification of reduction of size was 0-25% in 22 patients, 26-50% in 7 patients, 51-75% in 7 patients and 76-99% in 4 patients. Pain score (visual analogue score) reduced in patients having pain from 6.56 to 2.1.Complications: Post-procedure pain was the chief complaint, which subsided with analgesics. Two patients had neurological deficit (foot drop). Extensive necrosis in one case needed aspiration for symptom relief. Conclusions: Radiofrequency ablation of recurrent fibromatosis is a safe and effective treatment option. Procedure is well tolerated, with significant improvement in quality of life and good long-term locoregional disease and symptom control

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Poster 132: Portal Vein Embolization Can Be Performed Safely in the Outpatient Setting R.H. Siegelbaum, E.N. Petre, J.P. Erinjeri, G.I. Getrajdman, A. Covey. Radiology, Memorial Sloan Kettering Cancer Center, New York, NY. Objective: Patients undergoing PVE are typically admitted to the hospital post-procedure. Approximately 5 years ago, our group noted that most patients were discharged the following day without complication. This resulted in a change of practice, in which patients were routinely discharged home the same day following PVE. The goal of this study is to evaluate the safety of preoperative portal vein embolization (PVE) performed as an outpatient procedure. Methods: Retrospective review of our IRB-approved database identified all patients who underwent PVE as outpatient procedures between November 2010 and August 2015. The electronic medical record (EMR) was reviewed to evaluate for unplanned hospital re-admission within 30 days following PVE (i.e. for reasons other than planned liver resection). Peri-procedural complications were categorized according to CTCAE v.4 guidelines. Pre and post PVE laboratory values were recorded, as was whether or not the patient ultimately underwent planned liver resection. Results: The database review identified 93 PVE procedures performed during the study period. Of these, 65 (70%) were performed as outpatient procedures (i.e. patients were discharged the day of procedure). PVE was performed using spheric embolic agents and/or polyvinyl alcohol. The primary malignancy was colorectal (n=58), HCC (n=1), cholangiocarcinoma (n=1), leiomyosarcoma (n=1), GIST (n=1) and lymphoma (n=1). There were no significant changes in serum bilirubin and hematocrit pre- and post-PVE. There was one hospital readmission within 30 days (1/65, 1.6%), in a patient who presented with fever on post-procedure day one. Peripheral blood cultures on re-admission were positive for enterococcus faecium. The patient was managed with intravenous antibiotics and was discharged home on post-procedure day 3. Review of the EMR revealed that ERCP and stent placement was performed the week prior to PVE, causing colonization of the biliary tree. Review of fluoroscopic images reviewed from the case showed opacification of bile ducts while attempting to access a portal vein branch. Planned liver resection was performed in 56 patients (89%); 6 patients were unresectable due to disease progression, and in 1 patient there was insufficient growth of the future liver remnant to undergo planned liver resection. Conclusions: Portal vein embolization can be performed safely as an outpatient procedure in most cases, as less than 2% of patients were re-admitted within 30 days post-procedure. Caution should be taken in patients with recent instrumentation of the biliary tree. Poster 133: Nanosecond Pulsed Electric Field (nsPEF) Ablate Bone Tumor as a Palliative Therapy: A Preclinical Study on Canine Osteosarcoma X. Miao. The Department of Orthopedics, Zhejiang University, Hangzhou, China. Objective: our previous studies suggest that nanosecond pulsed electric field (nsPEF) is a novel minimal invasive and non-thermal ablation method that can induce apoptosis in.osteosarcoma MG-63 cells in vitro. The current study investigates the local and systemic antitumor efficacy of nsPEF on osteosarcoma in vivo with micro metastasis. Methods: Canine osteosarcomas were treated by nsPEF with puncture electrode at 40 Kv/cm electric field strength of 500 pulses. The survival time, tumor volume, serum alkaline phosphatase, joint capsule and lung metastasis were followed up to 6 months post nsPEF treatment. The efficacy was compared with no-treatment control and amputation surgery.

Poster 134: Analysis of Improved Microwave Applicators for Creating Directional Tissue Ablation Profiles J. Sebek1, W. Beard2, S. Curto1, P. Prakash1. 1Electrical and Computer Engineering, Kansas State University, Manhattan, KS; 2Clinical Sciences, Kansas State University, Manhattan, KS. Objective: Microwaves have emerged as an effective modality for percutaneous thermal ablation of large tumor volumes. Currently available microwave ablation (MWA) devices in clinical use have cylindrically symmetric radiation patterns, with no control of energy deposition along the angular expanse. Applicators with directional energy deposition patterns may simplify treatment of targets in proximity to critical structures. Our group recently presented such directional microwave applicator operating at 2.45 GHz (McWilliams et al., IEEE Trans Biomed Eng, 62(9):2144-50). In this study, we report on technical improvements to this design with the objectives of (i) minimizing device diameter to be suitable for clinical use (diameter d 13 G) and (ii) yielding larger ablation zones. An integrated simulation and experimental approach is employed to investigate improved device designs. Preliminary in vivo characterization of devices will be presented. Methods: The water-cooled directional MWA applicator consists of a coaxial monopole antenna, positioned within a hemi-cylindrical metallic tube, which serves as a reflector and constrains energy deposition to a preferred direction. We comparatively assessed the following modifications/augmentations to the antenna: (a) an “S-shaped” radiating tip, thereby increasing electromagnetic energy coupled to the target volume, (b) a metallic cap at the tip of the reflector, and (c) a shaped-reflector, thereby adjusting the distance between the reflector and radiating monopole. A coupled electromagnetic-heat transfer model implemented using the finite element method was used to simulate temperature profiles after 5 and 10 min ablation, with 65 and 85 W of applied power. The effects of varying blood perfusion levels on applicator performance were investigated. 2.5 mm (~13 G) diameter directional MWA antennas were fabricated and experimentally evaluated in ex vivo porcine

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muscle. Five experimental ablations were performed using each applicator design (original design and modified radiating tip) under the following experimental conditions: 5 and 10 min heating time; 65 and 85 W input power, yielding a total of 40 experiments. Dimensions of each experimental ablation zone were measured following tissue heating. Preliminary in vivo evaluation of directional MWA devices in a porcine liver model is in progress. Results: Modifying the antenna radiating tip to an S-shape had the greatest influence on ablation outcome. After 85 W, 10 min heating, computational models predicted ablation zones measuring 22mm (R, radially from applicator surface) and 35mm (L, axial length) with the optimized design, compared to 17 mm (R) and 25 mm (L) with the original design. In experiment, ablation zones measured 19.4r0.8 (R) mm for the improved device and 16.5r1.5 mm (R) with the original device. Changes of ablation zone dimensions with respect to applied power, time and blood perfusion were characterized. Conclusions: The improved directional MWA applicator design addressed the objectives of reducing the device size and extending its radial penetration depth. Further improvements can be attained by using cooling materials with lower electrical conductivity and shaping the reflector such that destructive interference is minimized. In vivo experimental characterization of the device is in progress and results will be presented at the congress. Poster 135: Radiofrequency-Assisted Intact Biopsy Device Improves the Characterization of Soft Tissue Tumors: A Pilot Study A. Iannessi, A. Pellegrin, A. Bertrand, A. Thyss. Interventional Oncology, Cancer Center, Antoine Lacassagne, NICE, France. Objective: Radiofrequency-assisted intact specimen biopsy (RFIB) has been introduced for percutaneous biopsy or removal of breast tumors. Using radiofrequency cutting, the system enables the radiologist to obtain an intact sample of the target lesion up to 2.5 cm3. Soft tissue tumors include sarcomas and benign tumors. Even though the lesion is small, the guidelines recommend a guided percutaneous biopsy rather than a surgical biopsy excision. However, fine pathology characterization can be challenging when the samples are small sized or tumors highly differentiated. To minimize the risk of underestimation we propose to assess the feasibility, tolerance and the efficiency of RFIB on soft tissue tumors. Methods: Patients with un-characterized soft tissue tumors were included within a 12-months period from May 2014. The multidisciplinary board including an interventional radiologist (IR) referred the patients after the evaluation. The surgeon marked the skin before the procedure that the IR could perform the percutaneous biopsy from the same pathway as the planned surgery. The procedure was performed using a 7-gauge RFIB device under local anesthesia and ultrasound guidance. The radiofrequency sampling was automated and lasted 10 seconds. The size of the sample was adapted from 0.7 cm3 to 2.5 cm3 according to the tumor presentation. According to the IDEAL recommendations, a critical evaluation was performed in order to report the technical feasibility, experienced pain on numerical scale, immediate complications and histologic analysis. Results: Patients with un-characterized soft tissue tumors were included within a 12-months period from May 2014. The multidisciplinary board including an interventional radiologist (IR) referred the patients after the evaluation. The surgeon marked the skin before the procedure that the IR could perform the percutaneous biopsy from the same pathway as the planned surgery. The procedure was performed using a 7-gauge RFIB device under local anesthesia and ultrasound guidance. The radiofrequency sampling was automated and lasted 10 seconds. The size of the sample was adapted from 0.7 cm3 to 2.5 cm3 according to the tumor presentation (figure 1). According to the IDEAL recommendations, a critical evaluation was performed in order to report the technical feasibility, experienced pain on numerical scale, immediate complications and histologic analysis. Conclusions: Radiofrequency-assisted intact biopsy of soft tumor combines the advantage of imaging-guided sampling and large surgical sample in a minimal invasive procedure. It is safe and well tolerated. In our opinion, the use of RFIB could be proposed as an alternative after a first non-contributive biopsy.

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Poster 136: Treatment Parameter and Tumor Anatomy Determinants of Change in Tissue Resistance During Irreversible Electroporation of Colorectal Cancer Metastases A. Moreland, E.N. Petre, D. Sarkar, S.B. Solomon, G. Srimathveeravalli. Memorial Sloan Kettering Cancer Center, New York, NY. Objective: Treatment of tissue with irreversible electroporation (IRE) induces changes in its electrical resistance (R). This study assessed treatment parameter and tumor anatomy determinants of change in R during IRE of mCRC in patients. Correlation between change in R and preliminary clinical outcomes was also examined. Methods: Intraprocedural voltage and current measurements recorded during IRE treatment (n=38) of mCRC (n=17) in 15 patients with uninterrupted pulse delivery was reviewed retrospectively. IRE was performed using 2-4 antennas at a median voltage of 2250V using 90 or 100Ps pulses. Intra-pulse and intra-treatment change in R were computed from the recorded data. The association between change in R and the following was analyzed: voltage, voltage to electrode spacing ratio, pulse length, number of pulses, energy deposited, tumor volume, tumor location, and technical success. Results: R decreased during most pulses and treatments (mean: -13.1 :; range: -33.9 to 3.7 :). Voltage >2500V decreased R more than lower voltages on an intra pulse (p < 0.0001) and intra treatment basis (p = 0.01). Voltage to electrode spacing ratio was a predictor only when spacing was >1.5 cm and voltage was >1500 V (p=0.01). Greater intra-pulse and intra-treatment energy delivery correlated with a greater decrease in R (p = 0.0004 and p = 0.04, respectively). Number of pulses, pulse length, and tumor volume were not predictive of change in R. A larger number of pulses demonstrated reduction in R during treatment of liver metastases than metastases in pelvis (p=0.001). Neither intra-pulse nor intra-treatment change in R was predictive of technical success as assessed on follow up PET-CT at the 3 month follow-up period. Conclusions: Voltage, energy, and tumor location correlated with decrease in R during IRE of mCRC. These parameters may therefore guide protocol planning and intraprocedural monitoring to define treatment endpoints. Further investigation is warranted to define the relationship between change in R and clinical outcomes following IRE of mCRC. Poster 137: The Evolution of Cryoablation Systems S. Ramadhyani, V. Vallapureddy, A. Zachman. R&D, Galil Medical Inc, Arden Hills, MN. Objective: Cryoablation is a clinically accepted modality for the minimally-invasive treatment of various malignant and benign tumors. This poster presents a historical review of the evolution of cryoablation systems from early liquid-nitrogen-based systems to current argon-based (Joule-Thomson) systems as well as ongoing efforts to develop closed-loop, tank-less systems. Methods: The review is based on our own experience developing cryoablation systems over the past 15 years, an Internet-based search of past and current commercially available cryoablation systems, and patent searches for descriptions of potential future closed-loop systems. Results: Significant engineering improvements in cryoablation systems over the past two decades have encouraged the progressive adoption of this treatment modality to address a wide range of cancers. The shift from liquid-nitrogen to argon-based systems has allowed for the development of small-gauge cryoablation needles that can be introduced percutaneously to virtually any target in the body. Advances in microelectronics and software have enabled the deployment of control consoles with sophisticated touch-screen user interfaces that offer both real-time equipment-diagnostic information as well as procedure-planning capabilities. Cryoablation procedures are now most often performed under image guidance using CT, ultrasound or MRI. There are on-going efforts to seamlessly integrate the cryoablation console to the imaging system to further facilitate

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efficient treatment. It is expected that future cryoablation systems will eliminate the logistical inconvenience of high-pressure gas tanks by operating in a closedloop mode. Such tank-less systems are under development. Conclusions: Cryoablation is being increasingly adopted for the minimally-invasive treatment of cancerous tissue, benign tumors and for palliative intervention. Early, large-diameter cryoprobes, based on liquid nitrogen, have been replaced by ultra-thin needles that utilize the Joule-Thomson cooling effect to achieve cryoablative temperatures. Technological advances have enabled the development of sophisticated, user-friendly systems that permit ablation of a wide variety of lesions with percutaneous introduction of the treatment needles. Future developments in cryoablation systems should further improve the usability of these systems and increase the speed and efficiency of this ablation modality.

W. Li, J. Zheng. Interventional Oncology, Beijing You’an Hospital, Capital Medical University, Beijing, China. Objective: To investigate the treatment efficacy of ablation-based hepatic sectionectomy in patients with advanced hepatocellular carcinoma Methods: We retrospectively collected information of patients with advanced hepatocellular carcinoma (HCC) treated with ablative sectionectomy. Intraoperative/ postoperative complications, recurrence-free survival and overall survival time were calculated and analyzed. Results: In total, 20 advanced HCC patients received ablative sectionectomy treatment in our center. The complication was rare. The operating time was also shorter. The 1, 3, 5-year recurrence-free survival and overall survival time were all superior over those of laparoscopic sectionectomy or sectionectomy by open surgery if compared by data from published literatures. Conclusions: Ablative sectionectomy may be a good novel treatment option for patients with advanced HCC instead of laparoscopic sectionectomy or open surgery. Further clinical studies with larger patient number and proper control arm are required to confirm this conclusion Poster 139: Effect of Change in Portal Blood Flow Rates on a Bipolar RF Ablation Device D.T. Johnson1, G.D. Dodd2. 1Radiology, University of Colorado Denver, Centennial, CO; 2Radiology, UC Denver, Aurora, CO. Objective: To investigate the effect of change in portal vein flow rates on the size and shape of ablations created by a bipolar radiofrequency (RF) ablation device. Methods: This study was exempt from review by the IACUC. An in-vitro bovine liver model perfused with autologous blood via the portal vein at three flow rates (60, 80, 100 ml/min/100g liver) was used to evaluate the effect of change in flow rates on the size and shape of coagulation created by a bipolar RF ablation device (In-Circle Monarch Bi-Polar probes, Model 03-48415-U, RFA Medical, Fremont, CA) powered at 85W until it impeded out (4-12 minutes). Four ablations, 2 with a bipolar and 2 with a monopolar RF ablation device (CC-1-117, Covidien, Boulder, CO, used as a control) were made in each of 5 livers perfused at each flow rate (10 ablations/device/flow rate). Short and long axis diameters (SAD and LAD) were measured from gross specimens and volume and sphericity index (SI) were calculated for each ablation. A general linear mixed model accounting for correlation within liver was used to evaluate the effects of flow on ablations. Results: The two ablation devices did not differ significantly in intercept for LAD (p=0.81) or SI (p=0.13), but did differ significantly in intercept for SAD (p<0.03) and Volume (p<0.01). Regarding the relationship with flow rate for each outcome, there were significant differences between Cool-Tip and InCircle in the responses to flow for each of the four outcomes (p<0.01 for each). The slopes (i.e. flow effects) for the InCircle device did not significantly differ from 0 for all four outcomes (p>0.05), whereas for the Cool-Tip device the slopes (flow effects) were significantly different from zero for all four outcomes (p<0.01 for each). The difference in the slopes for each of the measurements are shown in Figures 4-7. The average size and shape of the ablations for the InCircle device across all flow rates are SAD 4.3 cm (r 0.1 cm), LAD 4.2 cm (r 0.1 cm), volume 41.0 cm3 (r 1.8 cm3), and SI 1.1 (0.1), respectively. There was a significant difference in the variance between the two devices (p<0.001 for each) for all measurements with the InCircle device demonstrating far less variability than the monopolar RF device. Conclusions: Our study shows that the size and shape of coagulation necrosis created by a bipolar RF ablation device are not affected significantly by changes in portal vein blood flow rates. We also showed that the bipolar device demonstrates less variability in size and greater sphericity of ablation shape than a monopolar RF ablation device. The lack of susceptibility to changes in flow is similar to that reported for MW ablation devices and markedly different to the substantial susceptibility reported for monopolar RF ablation devices. The positive attributes of the bipolar RF ablation device could translate to improved treatment of hepatic tumors.

Poster 140: Improving Patient Safety in Interventional Oncology Through Advances in Image Acquisition and Processing Platform, Allowing for Drastic Reduction in Radiation Dose with Equivalent Image Quality S. Lekperic, C. Martinez, S. Nowakowski. Interventional Radiology, Mount Sinai Medical Center, New York, NY. Objective: In efforts to improve quality of healthcare, radiation safety has been paramount to Interventional Oncology where the cumulative radiation exposure is a true safety dilemma to the physician as well as to their oncology patients who often require multiple interventional fluoroscopic procedures. There are many variables which effects radiation dose, including software technology, operator techniques and settings, imaging system positioning, operator location, radiation protection equipment, and patient morphology. All factors listed are physician and patient variable except for software technology. In our study, we evaluate the radiation safety benefits of an advanced new image acquisition and processing software AlluraClarity (Philips, Best, The Netherlands) in reducing radiation dose in Interventional Oncology procedures. Methods: From July 2015 through November 2015, radiation-dose data were recorded for each fluoroscopic procedure in two adjacent angiography suites. Patient radiation dose exposure was evaluated using Cumulative dose-area product while scatter dose to operator was evaluated using two dosimeters worn by the operator and another at a fixed position on the C-Arm. While one room has standard fluoroscopic settings, the other room utilizes the advanced technology fluoroscopic setting. All cases were rated for level of difficulty by operators. For each Interventional Oncology procedure, a Wilcoxon-Mann-Whitney test was used to determine statistical significance. Results: All tested Interventional Oncology procedures showed a statistically significant radiation dose reduction using the advanced software technology in image acquisition and processing with no significant difference in fluoroscopy time or case difficulty. Averaging all oncolgy procedures tested, there was a 59% radiation reduction to patient along with a 69% radiation reduction to the physician performing the procedure. All test differences described had a p-value less than 0.01. Conclusions: These results demonstrate advances in the software technology x-ray delivery and processing system signficantly reduces radiation dose received by both patients and operators during Interventional Oncology fluoroscopic procedures without sacrificing image quality. Radiation Reduction with Advanced Acquisition and Processing Platform

Poster 141: Rethinking Hydrodissection during Percutaneous Microwave Ablation J. Smirniotopoulos1, M. Schiffman2. 1Radiology, New York Presbyterian Hospital/Weill Cornell Medicine, New York, NY; 2Interventional Radiology, New York Presbyterian Hospital/Weill Cornell Medicine, New York, NY. Objective: Percutaneous ablation is a well-established minimally invasive safe and effective technique for local tumor treatment. Cryoablation and radiofrequency ablation (RFA) are technologies that have been extensively studied, and their mechanisms of action are well understood. A key component of many of these procedures is hydrodissection, the application of a fluid interface creating a margin from vital structures to create a safe zone of ablation with a distance of 0.5-1 cm advocated in many papers. As microwave has become available, many operators have adopted this technology due to several of its afforded advantages including ease of use, speed, and decreased susceptibility to heat sink effects. Along with this shift, most operators have employed similar techniques for hydrodissection. However, due to the completely different mechanism of action of microwave compared to RFA and cryoablation, the degree of hydrodissection needed to protect surrounding structures from thermal injury with microwave ablation should be evaluated. Methods: Ex vivo bovine renal tissue was positioned in a clear container and 250cc of either room temperature normal saline, room temperature 5% dextrose in water (D5W), normal saline 12 degrees Celsius, and D5W 12 degrees Celsius was added to create four separate hydrodissection models. An Amica Microwave Ablation probe (HealthTronics) was inserted into the mid-renal parenchyma. Four thermometers were suspended in 1 cm intervals outward from the microwave ablation probe during each experiment, and ablations at 80W for 5 minutes were performed with temperatures recorded across all probes. Results: Five-minute ablations at 80W demonstrated the following: Normal saline room temperature model resulted in elevations of temperature from 19 to 31-degrees Celsius at 4 cm from the renal parenchyma. D5W room temperature model resulted

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Poster 138: Ablative Hepatic Sectionectomy in Patients with Advanced Hepatocellular Carcinoma

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in elevations of temperature from 21 to 27-degrees Celsius at 4 cm from the renal parenchyma. Cooled normal saline resulted in elevations of temperature from 12 to 17 degrees Celsius at 4 cm from the renal parenchyma. Cooled D5W resulted in elevations of temperature from 12 to 29 degrees Celsius at 4 cm from the renal parenchyma. Conclusions: This rudimentary model shows heat is transmitted through the renal parenchyma into the surrounding fluids, with diffuse yet homogeneous elevation in the fluid temperatures at up to the 4 cm measured. Although 0.5-1 cm may be sufficient for RFA with D5W hydrodissection due to the fluid’s low electrical conductivity, the same principle does not necessarily apply to the convective spread of heat in microwave surgery. These preliminary results suggest that much more robust hydrodissection spacing may be required to safely and routinely perform these procedures and avoid major complications such as neuromuscular damage and bowel injury. Additional investigation as to the preferred material and method for hydrodissection needs to be performed, with more accurate in vivo modeling. Future studies are underway in our lab to try to address these questions, but in the interim, additional care is suggested while doing these cases. Poster 142: Early Safety and Effectiveness of Thermosphere Microwave Ablation (Emprint) in the Percutaneous Treatment of Perivascular Liver Tumors J. Park, J. Kessler, A. Lee. City of Hope, Duarte, CA. Objective: Percutaneous image guided ablation is more commonly being performed in the treatment of primary and secondary hepatic tumors. Due to the unpredictability in shapes and sizes of ablation zones generated by current generation microwave ablation devices, treatment of tumors adjacent to vascular structures has presented challenges secondary to concerns of damage to the vessels as well as suboptimal ablation due to heat sink effects. Microwave ablation with thermosphere technology utilizes intra-procedural tissue permittivity feedback, enabling more controlled energy dispersion, spherical ablation zones and greater lesion predictability. In this study, we review the initial effectiveness and safety of percutaneous thermosphere microwave ablation in the treatment of perivascular liver tumors. Methods: A retrospective analysis was performed of all patients who underwent percutaneous image guided thermosphere microwave ablation (Emprint, Covidien) of perivascular (<5mm from adjacent vessels) hepatic tumors. Microwave ablations were performed under ultrasound guidance and CT monitoring utilizing a 2.45GHz (15cm) microwave antenna in either single or multiple overlapping ablations. Demographic data, biochemical and imaging records and treatment-related complications were reviewed. Post-procedural imaging was used to identify effectiveness of tumor ablations and patency of adjacent vessels pre- and post-treatment. Results: A total of 8 patients were identified for a total of 9 perivascular tumors treated. Thirteen major hepatic vessels (9 hepatic veins and 4 portal veins) were impacted by the ablations treatments. Average tumor diameter was 2.2 cm (range 1.3cm – 3.8cm). Average vessel size was 5.8mm (range 3.1mm – 9mm). Average distance of tumor to vessel was 0.8mm (0 – 4.5mm). MW antenna orientations were parallel to 9 vessels and perpendicular to 4 vessels. Final ablations zones ranged from 2.8cm – 5.6cm with each ablation zone completely in contact with the adjacent vessel and encompassing the targeted tumors and margins. Twelve vessels remained patent on follow up imaging. One vessel (3.1mm) centered within overlapping ablation zones was thrombosed as a result of the ablations. No significant side-effects or complications were present and all patients had stable hepatic biochemical profiles post-procedure. Short-term follow-up demonstrates complete ablation of the tumors and margins with only 1 case of local recurrence within an untreated zone of tissue adjacent to the inferior vena cava. Conclusions: Perivascular tumors directly abutting hepatic and portal venous structures were successfully treated utilizing the novel 2.45 GHz thermosphere microwave ablation system (Emprint, Covidien). Unlike previous generation microwave ablation devices, due to improved antenna design elements, the Emprint MWA system provides more predictable ablation zone shape and sizes enabling more precise treatment planning. Despite the challenging locations of the targeted tumors, no significant side-effects or complications were present. These short-term results suggest the safety and effectiveness of microwave ablation with thermosphere technology in the treatment of challenging perivascular hepatic tumors. Poster 143: Pulsed Microwave Ablation: A Multi-Parametric Study in Ex-Vivo Bovine Liver N. Tosoratti, S. Cassarino, C. Amabile. R&D, HS Hospital Service SpA, Aprilia, Italy. Objective: To characterize experimentally the coagulative performance of a 2.45GHz, 14G, internally cooled microwave applicator (AMICA-PROBE, HS HOSPITAL SERVICE SpA, Italy) using different energy delivery algorithms: fixed power (continuous) and intermittent (pulsed) delivery modes. Methods: 210 ablations were performed in ex-vivo bovine liver using different combinations of: coolant temperature (~5°C or ~20°C) and flow rate (~25 ml/min

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or ~100 ml/min); output power (P, ranging between 20 and 140W); overall treatment time (T = 3, 5, 10 or 15 minutes); duration of energy pulses (tON = 2, 4, 6 or 8s) and latency between consecutive pulses (tOFF = 3, 4, 6, 12 or 16s), leading to different duty cycles (DC, i.e. percentile energy activation time: 20%, 40%, 60% or 100% -for continuous mode ablations-). Results: For equal amounts of deposited energy (Ed), pulsed and continuous mode ablations provided similar ablation volumes (increasing linearly with Ed; see Fig.1.a)), but with different long and short axis measures: an appreciably higher sphericity index (i.e. short to long axis ratio; see Fig.1.b)) was observed in pulsed vs continuous mode ablations when using a combination of intensive cooling (water at 5°C; 110ml/ min flow rate), short pulses (tON=2s or 4s) and low DC (20% or 40%). Ablations of 52.5r2.5mm in the long axis and 46.0r1.0mm in the short axis were observed when pulsing energy with: DC=40%, tON=4s, P=140W and T=10min. Conclusions: These preliminary findings suggest that delivering microwave energy in short, high power pulses through adequately cooled applicators yields large and consistent ablation zones, with markedly increased sphericity compared to conventional energy delivery algorithms. The use of high intensity, fast energy pulsing may prove beneficial in terms of the treatment predictability and reproducibility, as the active heating contribution to the final ablation outcome is expected to prevail over the less controllable passive heating term. Further investigation is needed to characterize and optimize the pulsed microwave energy delivery algorithms performance in in vivo models and in tissues other than normal bovine liver.

The ablation short (D) and long (L) axis measurements were used to calculate the ablation volume (V=pi*D2 *L/6; see 1.a)) and linear sphericity index (S=D/L; see 1.b)) as a function of the energy (Ed= P*T*DC) deposited into ex-vivo bovine liver tissue using delivery algorithms characterized by different duty cycles; namely: continuous delivery (DC=100%, red circles), pulsed delivery with tON=6s and tOFF=4s (DC=60%, blue squares), pulsed delivery with tON=4s and tOFF=6s (DC=40%, green diamonds) and pulsed delivery with tON=2s and tOFF=8s (DC=20%, black crosses). All plotted data were obtained under the following conditions: intensive probe cooling (water at 5°C, 100ml/min flow rate); T ranging between 3min and 10min; P ranging from 20 to 160W. The coloured lines in the two plots provide the best numerical fits for each iso-DC data set (linear fit for V(Ed), power fit for S(Ed)). Poster 144: Colorized Heat-sensitive Phantom to Model Hydrodissection Fluids with Microwave Ablation (MWA) H. Narayanan, A. Mikhail, L. Jiang, J. Thai, P. Katti, V.P. Krishnasamy, A. Negussie, R. Seifabadi, E. Levy, B.J. Wood. Radiology, National Institute of Health, Arlington, VA. Objective: To assess the relative efficacy of hydrodissection using different fluid types during microwave ablation in a novel thermochromic phantom Methods: A thermochromic, tissue-mimicking phantom was synthesized using polyacrylamide and a chromogenic, temperature sensitive dye (color change threshold is 60°C). A 100 x 200 x 60 mm phantom box was custom fabricated with a 3D printer in order to simulate the hydrodissection gap between organs, created by a 5 mm thick spacer / insert. The gap was filled with either D5 water (D5W) or normal saline (NS). A 16G, 20 cm microwave ablation probe (HS Medical, Italy) was inserted into the phantom on one side of hydrodissection gap. Optical temperature probes were placed

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WCIO Abstracts

Poster 145: 3D Printing for Pre-/Intra-procedural Planning in Interventional Oncology A. Ghodadra1, R. Varma1, E. Santos1, K. Kim2. 1Radiology, UPMC, Pittsburgh, PA; 2Radiology, Yale, New Haven, CT. Objective: The objective of this exhibit is to review the basic types of 3D printing and their applications to procedure planning in Interventional Oncology, illustrate the process required to generate a printable file from DICOM data, and show how to identify the optimal printing method for a given application. Methods: The term 3D printing refers to an additive manufacturing process wherein a 3 dimensional object is created one layer at a time from a digital file. Recently, there has been a surge in the availability of consumer grade 3D printers. These relatively low cost, easy to use printers have made the use of 3D printing viable in the clinical setting. Solid and hollow models of vascular anatomy can be created to aid in planning for complex interventional oncology (IO) procedures. Results: A review of applications and potential advantages and disadvantages when compared to traditional visualization tools in IO is presented. A review of optimal patient and image selection is described. An overview of the major types and models of 3D printers, including fused deposition modeling and stereolithography, as well as printing materials is provided. The process of image segmentation and 3D model preparation is also reviewed. The selection of the optimal printer type and printing technique for IO applications is discussed. Finally, future studies needed and current limitations/future prospects of 3D printing in IO are discussed. Conclusions: The advent of desktop 3D printers presents the opportunity for the use of printed models of patient anatomy for procedure planning in IO. This review provides the reader with a concise overview of the applications of 3D printing in IO, various types of 3D printers, the process of generating 3D models and selection of the optimal printing method. Poster 146: Arms Down Cone Beam CT Hepatic Angiography Performance Assessment: Vascular Imaging Quality and Imaging Artifacts J.C. Durack1, A.J. Gonzalez Aguirre1, G. Avignon2, E.N. Petre1, F.E. Boas1, C.T. Sofocleous1, J.P. Erinjeri1, K.T. Brown1, L.A. Brody1, S.B. Solomon1. 1 Radiology, Memorial Sloan Kettering Cancer Center, New York, NY; 2 GE Health Care, Wauwatosa, WI. Objective: Arterial phase cone beam CT (A-CBCT) during catheter-directed liver interventions is commonly performed with the patient’s arms above the head to mitigate the impact of bone scatter on imaging quality. Repositioning the arms can interrupt workflow and increase procedure time. We compared A-CBCT vascular imaging quality and imaging artifacts with arms by the side versus above the head. Methods: We conducted an institutional review board approved retrospective evaluation of 101 consecutive catheter-injected hepatic A-CBCTs (43 arms up, 48 arms down) acquired on flat panel detector angiography systems (Innova 4100, GE Healthcare, Waukesha, WI). Arterial anatomy was independently evaluated on 2D and 3D images by two readers. Vessel visualization scores (VVS) from 1 (poor) to 3 (excellent) were recorded for each vessel order from 1-6 (celiac trunk to subsegmental hepatic arteries). Streak artifacts, motion artifacts, image non-uniformities and artifacts related to hyperdense structures were graded from 1 (none) to 3 (significant impact). Motion was graded from 0 (none) to 3 (high). Chi squared tests were used to compare proportions of VVS at each order of the arterial anatomy. Univariate and multivariate analyses were performed to assess body mass index (BMI), respiratory motion, and cardiac motion in relation to arm position. Results: Streak artifacts were greater in A-CBCT studies performed with the arms down compared to arms up (p < 0.005), in part due to physiological monitoring cables traversing the patient when arms were down. For all other artifact types studied there were no statistical differences between the two groups. Regardless of arm position, arterial vessels through the 6th order were visualized. No statistically significant differences in VVS were found between arms down and arms up A-CBCT except for 6th order 2D arterial imaging for one of the readers (p=0.019), though this difference was not apparent on 3D reconstruction analysis. Inter reader agreement was 86% with a substantial Kappa value of 0.64 for VVS. Respiratory motion and obesity (BMI>30, equally distributed between groups) (p < 0.005) influenced VVS on both univariate and multivariate analyses. Conclusions: A-CBCT angiography performed with the arms raised above the head is not superior for clinically relevant vascular visualization compared to imaging performed with the arms by the patient’s side. Obesity and respiratory motion significantly impacted vascular imaging in both groups.

WCIO Abstracts

at varying distances from the electrode using a custom needle guide to ensure accurate depth and separation within the phantom. Three temperature probes were placed at varying distances from the MWA needle. One was placed at 10 mm not protected by the hydrodissection gap. Two were placed at 10 and 20 mm away protected by the gap. Temperature was measured as a function of distance from the microwave ablation probe, with and without hydrodissection with specific fluids. Microwave ablation was performed at 20 watts for 5 minutes with an expected ablation zone size of 27 mm x 20 mm as per IFU. Phantoms were sectioned and analyzed for gradations in color changes previously validated to correspond to specific temperatures. Results: A 5 mm gap (hydrodissection plane) filled with D5 water yielded comparable temperature rises to those when filled with NS for temperature probes at 10 mm away [figure 2]. Temperature rises with D5 and NS were: 33.1 vs 30.7 °C for the unprotected probe, and 11.4 and 12.2 °C for the 10mm protected probe, and 3.6 vs 5.5 °C for the 20mm protected probe. Conclusions: Hydrodissection with NS instead of D5W demonstrated very similar temperature changes in this benchtop thermochromic phantom model with phantom material that changes colors calibrated to temperatures. This is different than radiofrequency ablation where D5W has been shown to be more thermally protective compared with normal saline. Further evaluation of variables such as the thermal vs electrical conductivity of each fluid and the thermal sink into the volume of fluid are warranted prior to any validation in a preclinical model to inform clinical practice.

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e110

Poster 147: Evaluation of Carcinoembryonic Antigen (CEA) Density as a Prognostic Factor for Percutaneous Ablation of Pulmonary Colorectal Metastases

WCIO Abstracts

Y. Huo1, D. Glenn1, M. Power1, J. Zhao2, W. Liauw3, D. Morris2. 1 Department of Radiology, St George Hospital, UNSW Australia, Kogarah, NSW, Australia; 2Department of Surgery, St George Hospital, UNSW Australia, Kogarah, NSW, Australia; 3Cancer Care Centre, St George Hospital, UNSW Australia, Kogarah, NSW, Australia. Objective: To evaluate the prognostic value of carcinoembryonic antigen (CEA) Density in addition to clinicopathological factors in patients who undergo percutaneous ablation of pulmonary metastases from colorectal cancer. Methods: This study includes all patients who have undergone percutaneous ablation of colorectal pulmonary metastases at St George Hospital since 2000. CEA Density was calculated as: “pre-ablation absolute serum CEA (ng/mL) /volume of all lung metastases [mm3]”. The median CEA Density was the cut-off for high and low groups. Cox-Regression was used for univariate and multivariate analysis to determine prognostic factors for survival. Logistic regression was used to identify clinical factors associated with CEA Density. Results: A total of 85 patients were followed for a median of 27 months. The median survival for patients with a low CEA Density and a high CEA Density was 44.3 months and 25.7 months, respectively (p=0.002). A high CEA Density was significantly associated with a worse overall survival compared to a low CEA Density in univariate analysis, and when adjusted for age and disease free interval (adjusted HR: 2.12, 95% CI 1.22-3.70, p=0.002). Another independent predictor associated with survival was the interval between primary resection of the colorectal carcinoma and first ablation, whereby a duration >24 months was associated with a better survival compared to a shorter interval (0-24 months) (adjusted HR: 0.55, 95% CI: 0.31 – 0.98, p=0.04). Moreover, a longer disease free interval (>24 months) was significantly likely to have a low CEA Density compared to a shorter interval (0-24 months) (adjusted OR: 0.29, 95% CI: 0.11 – 0.77, p=0.01). Conclusions: Serum CEA Density and interval between primary resection of a colorectal carcinoma and pulmonary ablation are independent prognostic factors for overall survival. Table 1. Multivariate analysis using Cox Regression for Overall Survival (OS) and overall disease free survival (DFS)

*p<0.05, **p<0.01, ***p<0.001 CEA, carcinoembryonic antigen; HR, Hazard Ratio

WCIO Abstracts

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JVIR

Poster 148: CT-Guided Microcoil Fiducial Placement for Small or Subsolid Pulmonary Nodule Localization in Thoracoscopic Wedge Resections F. Edalat1, M.S. Sancheti2, C.A. Gilliland1. 1Radiology and Imaging Sciences, Emory University, Atlanta, GA; 2Surgery, Emory University, Atlanta, GA. Objective: A variety of techniques exist for localizing pulmonary nodules for video-assisted thoracoscopic surgery (VATS) wedge resection with their own set of limitations and complications. Small and subsolid pulmonary nodules present a unique challenge for thoracic surgeons given their small size and non-palpability. The purpose of this study is to study the safety and efficacy of a new method of localizing subcentimeter or subsolid pulmonary nodules via CT-guided microcoil fiducial placement for VATS wedge resection which overcomes limitations of existing localization techniques. Methods: Retrospective, IRB-approved study of 9 patients and 10 CT-guided microcoil fiducial placement. On the same day and prior to VATS wedge resection, CT-fluoroscopy was used to place a microcoil distal and proximal to the pulmonary nodule of interest (Fig 1). Findings and procedure details were communicated to the thoracic surgeon by the interventional radiologist. Intra-operatively, after gaining access to the pleural cavity, the thoracic surgeon used fluoroscopy to localize the fiducial markers and performed a wedge resection. Results: 9 patients (mean age 65.2, SD 8.1; 78% female; 2/9 with emphysema) underwent 10 CT-guided microcoil fiducial placements. All fiducial markers were successfully placed without any complication. VATS wedge resection was performed with successful localization of all fiducial markers without any complication. Fluoroscopy of resected specimen revealed presence of all fiducial markers and histopathology revealed presence of pathology of interest without interference from the fiducial procedure on pathological diagnosis. Mean pulmonary nodule diameter was 11.6 mm (range 2-20 mm) with 4/10 being ground-glass (GG), 2/10 solid and GG, and 4/10 solid nodules. Mean pulmonary nodule-to-visceral pleura distance was 29 mm (range 11-62 mm). 5/10 nodules were in the LUL, 2/10 were in the LLL, 2/10 in the RLL, and 1/10 in the RLL. Histopathology revealed 5/10 nodules to be lung adenocarcinoma, 2/10 metastatic adenocarcinoma, 2/10 chronic interstitial pneumonitis, and 1/10 atypical adenomatous hyperplasia. Mean hospital length of stay was 1.7 days (SD 1.0). Conclusions: CT-guided microcoil fiducial placement in the immediate vicinity of a pulmonary nodule is a safe and effective tool for directed VATS wedge resection.

Author Index A

Boas, F. E - Poster 27, Poster 94, Poster 97, Poster 146

Chen, George G - Poster 123 Chen, James X - Paper 34

Abdel aal, Ahmed Kamel - Poster 35

Bodager, Brandon - Poster 66

Chen, Johnson O - Poster 74

Abdelsalam, Mohamed E - Poster 13

Bonomo, Guido - Paper 35

Chen, Min-Hua - Paper 1, Paper 2

Abel, E. Jason - Poster 14, Poster 16,

Bosch, Maurice AAJ - Paper 20, Paper 22

Chevallier, Patrick - Paper 36

Boulin, Mathieu - Poster 2

Chivate, Rahul Shantikumar - Poster 32,

Poster 17 Accardo, Catello - Poster 39, Poster 106

Brace, Christopher - Paper 15, Paper 16,

Poster 95, Poster 117

Achakzai, Basit - Poster 77

Paper 24, Poster 4, Poster 57,

Choi, Hailey - Poster 92

Achakzai, Basit K - Poster 120

Poster 124

Chon, Andy - Poster 33

Dupuy, Damian Edward - Paper 41, Poster 9, Poster 24 Durack, Jeremy C - Paper 19, Poster 27, Poster 146 Duran, Rafael - Paper 25, Paper 11, Poster 90 Dybul, Stephanie - Poster 11

E

Adamo, Robert - Poster 84

Brilliant, Kate - Poster 24

Chopra, Rishi - Poster 108

Ahmad, Asma - Paper 7

Brinckerhoff, Susan - Poster 82

Choyke, Peter - Poster 78

E. Paul, Wileyto - Paper 34

Ahrar, Kamran - Paper 38, Poster 13,

Brody, Lynn A - Poster 27, Poster 94,

Christos, Paul J - Paper 30

Edalat, Faramarz - Poster 148

Cobb, Benjamin W - Paper 30

El-Haddad, Ghassan - Paper 34

Poster 126, Poster 146

Poster 76 Al-Natour, Mohammed Said - Poster 7

Brountzos, Elias - Poster 3, Poster 119

Coleman, Jonathan - Paper 19

Elkine, Elena B - Paper 4

Alago, William - Poster 97

Brown, Anthony - Paper 39

Collettini, Federico - Paper 5

Ensor, Joe - Paper 38

Alexander, Marci - Poster 128

Brown, Daniel - Paper 7, Paper 13,

Collins, Scott - Paper 41

Erinjeri, Joseph P - Paper 19, Poster 27,

Allgeier, Sarah Hicks - Poster 54

Poster 113, Poster 115

Collins, Zachary - Poster 48

Poster 126, Poster 132, Poster 146

Amabile, Claudio - Poster 143

Brown, Karen T - Poster 27, Poster 146

Contractor, Sohail - Poster 72

Eschelman, David - Poster 84, Poster 85

Amancio, Camila Trolez - Poster 23

Bruel, Brian M - Poster 111

Contreras, Francisco - Poster 65

Esposito, Guiseppe - Poster 22

Ambrosino, Pasquale - Paper 27, Poster 39,

Brunner, Michael C - Paper 4, Poster 104

Cornelis, François - Paper 40

Eweka, Abie - Poster 50, Poster 108

Brylka, Douglas O - Poster 74

Covey, Anne - Poster 27, Poster 126,

Poster 45, Poster 46, Poster 47 An, Xiao - Paper 17, Poster 8

Buchowski, Jacob - Poster 111

Arce-Lara, Carlos - Paper 39

Bui, James T - Poster 69, Poster 70

Cox, Veronica L - Poster 79

Ardon, Roberto - Paper 11, Poster 81

Bullen, Jennifer - Poster 1

Crawford, Kevin - Poster 44

Fahrbach, Thomas - Poster 48

Atoria, Coral L - Paper 4

Busto, Giuseppina - Poster 39, Poster 106

Cristescu, Mircea M - Paper 24, Poster 4,

Fancellu, Alessandro - Paper 21,

Atwell, Thomas D - Poster 83, Poster 96

Butani, Devang - Poster 25

Averill, Sarah L - Poster 16 Avignon, Gregoire - Poster 146

C

Poster 132

F

Poster 104, Poster 124

Faria, Silvana C - Poster 79

Curto, Sergio - Poster 134

Fedi, Massimo - Poster 130

Ayalew, Assefa M - Poster 83

Feldstein, David Christopher - Poster 84

Azimov, Neyra - Poster 108, Poster 109

Cacace, Luigi - Poster 39

Azrumelashvili, Tamta - Paper 46,

Cai, Liqun - Paper 19

Poster 55, Poster 125

Callstrom, Matt - Poster 83, Poster 96,

Baadh, Amanjit - Poster 49, Poster 50 Baghai, Shahine - Poster 129

D

Feurer, Irene - Paper 7 Filippiadis, Dimitrios - Poster 3,

Das, Dola - Poster 7

Poster 11, Poster 119

De Baere, Thierry - Paper 40

Fine, Gabriel C - Poster 27

Camacho, Juan C - Poster 15, Poster 102

de Greef, Martijn - Paper 20, Paper 22

Finkelstein, Paige E - Paper 26

Campbell, Janice - Poster 116

DeBacker, Sarah - Poster 48

Fleckenstein, Florian Nima - Paper 11,

Carberry, George - Paper 15, Paper 16,

Dedes, Ioannis - Poster 112

Poster 111

B

Paper 23, Poster 101

Cristiana, Fodor - Paper 35

Poster 90

Paper 24, Poster 4, Poster 121,

Della Vigna, Paolo - Paper 35

Flister, Michael - Paper 18, Paper 10

Poster 124

Denys, Alban - Paper 36

Flug, Jonathan - Poster 108, Poster 109

Baird, Grayson - Poster 9, Poster 24

Caridi, Theresa - Poster 92

Deschamps, Frédéric - Paper 40

Francesco, Giurazza - Paper 43

Bakare, Vishal - Poster 32, Poster 117

Carmignani, Luca - Poster 130

Di Lieto, Marco - Poster 130

Frangakis, Constantine - Poster 10

Bakre, Vishal - Poster 95

Carr, Christie - Poster 67

Dias, Larissa Tamara Praude - Poster 23

Frank, Victoria - Paper 41, Poster 24

Ballicu, Nicola - Paper 21, Paper 23,

Carteret, Thibault - Paper 40

Dittmar, Kristin - Poster 34

Fristachi, Raffaele - Poster 39

Cassarino, Simone - Poster 143

Do Minh, Duc - Poster 91

Fu, Jing-Jing - Paper 1, Paper 2

Cazzato, Roberto - Paper 43

Do, Richard K - Poster 94, Poster 97

Bailey, Christopher William - Poster 42

Poster 101 Banovac, Fil - Paper 7, Paper 13,

Cercek, Andrea - Poster 94

Dodd, Gerald D - Paper 44, Poster 139

Basafa, Ehsan - Poster 28

Cerri, Giovanni Guido - Poster 23

Dong, Weihua - Paper 17

Batistaki, Chrysanthi - Poster 119

Chao, Samuel T - Poster 111

Drevelegas, Antonios - Poster 112

Gaba, Ron Charles - Poster 69, Poster 70

Beard, Warren - Poster 134

Chapiro, Julius - Paper 8, Paper 25,

Dreyer, Stephen Edward - Poster 76

Gade, Terence - Poster 41, Poster 43,

Poster 113, Poster 115

G

Beheshti, Michael - Poster 60

Paper 5, Paper 11, Paper 32, Poster 80,

Duan, Xu-hua - Poster 98, Poster 99

Bertrand, Anne-Sophie - Poster 135

Poster 81, Poster 90, Poster 91

DuBay, Derek - Poster 35

Gai, Yongkang - Poster 5

Duncan, James - Paper 8, Paper 32,

Gala, Kunal - Poster 32, Poster 95,

Best, Sara - Poster 14, Poster 16, Poster 17

Charalel, Resmi A - Paper 30 Charalel, Resmi Ann - Poster 58

Poster 80, Poster 81

Poster 56

Poster 117

e112

Author Index

Gallo, Paolo - Paper 27, Poster 39, Poster 45,

Hamm, Bernd - Paper 5

Karam, Jose A - Poster 13

Lee, Aram - Poster 142

Han, Xinwei - Poster 114

Karuppasamy, Karunakaravel - Poster 1

Lee, Fred - Paper 15, Paper 16, Paper 6,

Gangi, Afshin - Poster 111

Haroun, Reham - Paper 25

Kato, Mina - Poster 53

Paper 24, Poster 4, Poster 14,

Gao, Song - Paper 45

Hasegawa, Takaaki - Poster 53

Katti, Prateek - Poster 144

Poster 16, Poster 17, Poster 57,

Gardner, Carly S - Paper 38

Hawkins, Matthew - Poster 110

Katz, Alan - Poster 87, Poster 88

Gavane, Somali - Poster 94

Hayano, Koichi - Poster 86

Kelekis, Alexis - Poster 3, Poster 11,

Gebauer, Bernhard - Paper 9, Paper 5,

Hetzel, Scott - Paper 15

Poster 46, Poster 47, Poster 106

Poster 119

Poster 124, Poster 128 Lee, Jae Wook - Poster 18 Leite, Claudia Costa - Poster 23

Paper 11, Paper 32, Poster 80,

Hill, Jacqueline - Poster 48

Kelekis, Nikolaos - Poster 3, Poster 119

Lekperic, Safet - Poster 140

Poster 81, Poster 91

Hinshaw, J Louis - Paper 6, Poster 14,

Keller, Scott B - Poster 34

Lemons, Steven - Poster 48

Geevarghese, Sunil - Paper 7

Poster 16, Poster 17, Poster 124,

Kemeny, Nancy E - Poster 94

Levine, Matthew H - Poster 41

Geisel, Dominik - Paper 5

Poster 128

Kenyon, Brendan - Poster 24

Levy, Elliot - Poster 144

Hiremath, Satchi - Poster 66

Kessler, Jonathan - Poster 142

Lewandowski, Robert J - Poster 82

Ho Sohn, Jae - Paper 11, Poster 90

Khanna, Vinit - Poster 87, Poster 88

Lewis, Valerae O - Paper 38

Hoffmann, Jason Charles - Poster 49,

Kierans, Andrea S - Poster 74

Li, Wei - Poster 138

Kies, Darren - Poster 15, Poster 44

Li, Weiguo - Poster 82

Kim, Alexander Y - Poster 22, Poster 51,

Liauw, Winston - Poster 147

Georgiades, Christos - Poster 10, Poster 110 Geschwind, Jean-Francois - Paper 8, Paper 25, Paper 11, Paper 32,

Poster 50, Poster 108, Poster 109

Poster 80, Poster 81, Poster 90,

Hohenwalter, Eric - Poster 11, Poster 59

Poster 91

Hossbach, Martin - Poster 28

Poster 68, Poster 92, Poster 93,

Libertino, John Andre - Poster 12

Howard, Travis D - Poster 96

Poster 129

Lim, Marc - Poster 52

Getrajdman, George I - Poster 27, Poster 132 Ghodadra, Anish - Poster 6, Poster 127, Poster 145 Giambrone, Ashley - Poster 58 Giannessi, Sandro - Poster 130

Howk, Kreg - Paper 45

Kim, Dong-Hyun - Paper 33

Lim, Sierin - Poster 24

Huang, Steven Y - Paper 38

Kim, Hongho - Poster 18

Limback, Joseph - Poster 65

Humphrey, John - Poster 12

Kim, Hyun S - Paper 31, Poster 15,

Limninart, Narisara - Poster 71

Hunt, Stephen - Poster 41, Poster 43, Poster 56

Poster 73, Poster 102, Poster 118 Kim, Kevin - Poster 5, Poster 6,

Giantonio, Bruce - Paper 37

Hunt, Suzanne - Poster 48

Poster 110, Poster 127, Poster 145

Gilliland, Charles A - Poster 148

Huo, Ya Ruth - Poster 147

Kim, Namkug - Poster 18

Giordano, Renato - Poster 106

Hussain, Saad - Poster 80

Kim, Nancy - Poster 93

Lin, Manxia - Poster 75, Poster 103 Lin, MingDe - Paper 8, Paper 25, Paper 11, Paper 32, Poster 80, Poster 81, Poster 90, Poster 91 Lipnik, Andrew - Paper 7, Paper 13,

Giri, Shivraman - Poster 82

Kinbara, Yuki - Poster 53

Glenn, Derek - Poster 147

Kingsbury, James M - Poster 42

Lipnik, Andrew J - Poster 69, Poster 70

Goel, Akshay - Poster 126

Kishore, Sirish - Poster 94

Lischalk, Jonathan - Poster 92

Goel, Mahesh - Poster 95

Iannessi, Antoine - Poster 135

Klapperich, Marki - Poster 4

Liu, Bo - Poster 65

Gogineni, Venkateswara - Paper 18,

Inaba, Yoshitaka - Poster 53

Klein, Nina - Paper 3, Paper 42

Liu, Cuihong - Paper 11

Iovino, Vincenzo - Poster 106

Kodama, Hiroshi - Paper 45

Loaiza-Bonilla, Arturo - Paper 37

Iqbal, Saad - Poster 48

Koirala, Nischal - Poster 7

Lokken, R. Peter - Poster 69, Poster 70

Kokabi, Nima - Poster 15, Poster 73,

Long, Jeremiah - Poster 111

Paper 10, Poster 59 Gonda, Elizabeth A - Poster 82

I

Gonen, Mithat - Poster 94, Poster 97 Gonsalves, Carin - Poster 84, Poster 85

J

Gonzalez Aguirre, Adrian Jose Poster 97, Poster 146

Poster 102

Lopez, Emilio - Poster 110

Koran, Mary Ellen - Paper 13, Poster 115

Louie, John - Poster 40 Lu, David - Poster 31 Lubner, Meghan - Paper 6, Poster 14,

Jaberi, Arash - Poster 89

Kostantos, Chrysostomos - Poster 3

Gordon, Andrew Christian - Poster 82

Jagtap, Jaidip M - Paper 18, Paper 10

Kothary, Nishita - Paper 34

Gorodetsk, Boris - Poster 91

James, Trent - Poster 48

Krishnasamy, Venkatesh P - Poster 144

Greenwood, Taylor J - Paper 12

Jang, Benjamin - Poster 48

Kulkarni, Suyash - Poster 32, Poster 95,

Griffith, April - Poster 109

Jaramillo, Carlos Alberto - Poster 122

Grigoriadis, Stavros - Poster 119

Jennings, Jack W - Paper 12, Poster 111

Groeniger, Joshua - Poster 51

Jeong, Joanna - Poster 67

Gu, Yangkui - Paper 19

Jiang, Liwei - Poster 144

Kusin, Samuel - Poster 13, Poster 76

Guenther, Enric - Paper 3, Paper 42

Jo, Jonathan - Poster 58

Kwak, Jin Tae - Poster 78

Gueyikian, Sebouh - Poster 66

Johnson, D Thor - Paper 44, Poster 139

Kwan, Sharon W - Paper 4

Guiu, Boris - Paper 36, Poster 2

Johnson, Philip - Poster 48

Gupta, Amar Chandra - Poster 1

Jonczyk, Martin - Paper 5

Gupta, Sanjay - Paper 38, Poster 79

Joshi, Amit - Paper 18, Paper 10

Gurajala, Ram Kishore - Poster 1

Habibollahi, Peiman - Poster 41

Kurup, Anil Nicholas - Poster 83, Poster 96

Poster 128 Ludwig, Johannes Maximilian - Paper 31, Poster 5 Lupi, Martina - Poster 130

L

Lynskey, G. Emmett - Poster 92

M Madaelil, Thomas - Paper 12 Maddineni, Shekher - Poster 52 Madoff, David C - Paper 30, Poster 58

Laeseke, Paul F - Paper 6

Mahvash, Armeen - Poster 79

LaGratta, Maria D - Poster 74

Majdalany, Bill S - Poster 54

Kabus, Sven - Paper 8

Langenstroer, Peter - Poster 11

Makrmalla, Abouelmagd - Poster 67

Kachura, John Robert - Poster 89

Lapuyade, Bruno - Paper 40

Manzano, Wilfred - Paper 8, Paper 32,

Kakarala, Bharat - Poster 10

Larson, Andrew C - Paper 33, Poster 82

Kannengiesser, Stephan A.R - Poster 82

Lea, William - Paper 39, Poster 59

H Poster 125

Poster 105, Poster 117, Poster 131

Poster 16, Poster 17, Poster 124,

Lacayo, Eduardo Alejandro - Poster 22

K Habib, Nagy - Paper 46, Poster 55,

Poster 113, Poster 115

Poster 80, Poster 81 Martinez, Cynthia - Poster 140

Author Index

e113

Mason, Peter - Paper 15

Nasto, Aurelio - Paper 27, Poster 39,

Pietanza, Maria C - Poster 97

Salem, Riad - Paper 34, Poster 82, Poster 90

Massaroni, Carlo - Paper 43

Poster 45, Poster 46, Poster 47,

Pinjaroen, Nutcha - Poster 61, Poster 71

Matin, Surena - Poster 13

Poster 106

Pinto, Peter - Poster 78

Sana, Barindra - Poster 24

Matsubara, Hisahiro - Poster 86

Negussie, Ayele - Poster 144

Podrabsky, Petr - Paper 9

Sancheti, Manu S - Poster 148

Mauer, Elizabeth A - Paper 30

Nicholas, Fidelman - Paper 34

Polnaya, Ashwin - Poster 32, Poster 95,

Santos, Ernesto - Poster 145

Mauri, Giovanni - Paper 35

Niu, Lizhi - Paper 14, Poster 107

Maxwell, Aaron W.P - Poster 9

Nocerino, Elisabetta - Paper 15, Paper 16,

Poster 105, Poster 117, Poster 131

Sarkar, Debkumar - Poster 136

Power, Mark - Poster 147

Sato, Takami - Poster 84, Poster 85

Powerski, Maciej Janusz - Paper 9

Sato, Yozo - Poster 53

Prakash, Punit - Poster 134

Savic, Lynn Jeanette - Poster 91

McArthur, Heather - Paper 19

Primmer, Michael - Paper 41

Savin, Jeffrey - Poster 116

McCabe, Sam - Poster 52

Prologo, John D - Poster 44, Poster 110

Savin, Michael - Poster 116

Pusceddu, Claudio - Paper 21, Paper 23,

Sawas, Ayman - Poster 25

Maybody, Majid - Poster 27 Mazioti, Argyro - Poster 3

Paper 24, Poster 57 Nowakowski, Scott - Poster 140

O

McLennan, Gordon - Poster 7 McVinnie, David - Poster 120

O’Dell, Matthew Cody - Poster 65

Melis, Luca - Paper 21, Paper 23,

Odisio, Bruno C - Poster 79

Poster 101

Schatzman, Carmen - Poster 67

Poster 101

Schembri, Valentina - Paper 36, Poster 2

Oh, Sang Young - Poster 18

R

Schena, Emiliano - Paper 43 Schernthaner, Ruediger - Paper 25,

Mendoza, David - Poster 122

Ohira, Gaku - Poster 86

Menezes, Marcos Roberto - Poster 23

Olowokure, Olugbenga - Poster 67

Rahman, Akm - Poster 50

Metz, David - Paper 34

Olsen, Jonathan - Poster 116

Rai, Ayushi - Poster 7

Schiffman, Marc - Poster 141

Meyer, Jeffrey - Poster 111

Omary, Reed A - Paper 13, Poster 113,

Ramadhyani, Satish - Poster 137

Schlachter, Todd - Paper 11, Poster 91

Ramchand, Tekchand - Poster 118

Schmidt, Thomas - Paper 5

Miao, Xudong - Poster 133

Poster 115

Paper 11, Poster 90

Mikhail, Andrew - Poster 144

Onoda, Yui - Poster 53

Ramos, Jeanne - Paper 36

Schmit, Grant D - Poster 83, Poster 96

Mikus, Paul - Paper 42

Orloff, Marlana - Poster 84, Poster 85

Rashid, Shayan - Poster 80

Schmitt, Antonin - Poster 2

Milisavljevic, Ana - Paper 7

Orsi, Franco - Paper 35

Ravenda, Paola simona - Paper 35

Schmitz, John J - Poster 83, Poster 96

Miller, Akemi - Poster 68

Osborne, Joseph - Poster 94

Ray Jr., Charles E - Poster 69,

Schnapauff, Dirk - Paper 9, Paper 5

Miller, Frank H - Poster 82

Owen, Joshua - Poster 69, Poster 70

Schubert, Gerald - Paper 20

Poster 70

Mills, David - Poster 24

Redden, David - Poster 35

Schwahn, Denise - Paper 15

Ming, Kuang - Paper 28, Paper 29,

Reddy, Shilpa - Poster 56

Schwartz, Scott - Poster 77

Reiner, Eric - Paper 8

Sebek, Jan - Poster 134 Segal, Neil H - Poster 94

P

Poster 62, Poster 63, Poster 64 Mironov, Oleg - Poster 89

Pacini, Patrizio - Poster 130

Reppas, Lazaros - Poster 119

Mittal, Sameer - Poster 50

Pagliari, Andrea - Poster 130

Riaz, Rehan - Poster 120

Seifabadi, Reza - Poster 28, Poster 144

Miyauchi, Hideaki - Poster 86

Palmer, Drew A - Poster 12

Ries, Mario G - Paper 20, Paper 22

Seo, Joon Beom - Poster 18

Mizandari, Malkhaz - Paper 46,

Pan, Kevin - Poster 85

Rilling, William - Poster 11, Poster 59,

Shaaya, Elias - Poster 129

Poster 55, Poster 125

Pandit - Taskar, Neeta - Poster 97

Shady, Waleed - Poster 94, Poster 97

Poster 82

Mondschein, Jeffrey I - Paper 37

Parchur, Abdul K - Paper 18, Paper 10

Ristagno, Ross - Poster 67

Shah, Shimul - Poster 67

Moonen, Chrit TW - Paper 20,

Park, David - Poster 59

Robinson, Amie - Poster 48

Shahid, Muhammad Usman - Poster 72

Park, Hee Jun - Poster 18

Robinson, Clifford G - Poster 111

Shaikh, Raja - Poster 100

Moradzadeh, Nathaniel David - Poster 40

Park, Jinha - Paper 43

Robson, Piera - Poster 126

Sharma, Ashwani - Poster 87, Poster 88

Moreland, Anna - Poster 136

Park, John - Paper 43, Poster 142

Rochon, Paul - Poster 109

Sharma, Gayatri - Paper 18, Paper 10

Morinaga, Hiroyuki - Poster 53

Park, Keun Chan - Paper 41, Poster 24

Rock, Lindsay - Poster 48

Shetty, Nitin - Poster 32, Poster 95,

Morris, David - Poster 147

Park, Wooram - Paper 33

Rohr, Aaron - Poster 48

Morris, Jonathan M - Poster 83,

Patel, Chirag - Poster 77, Poster 120

Rose, Steven C - Paper 34

Shi, Xiao - Poster 79

Patel, Maharshi - Poster 60

Rotman, Jessica A - Paper 30

Shuto, Kiyohiko - Poster 86

Patel, Paresh Gordhanbhai - Poster 95,

Rubert, Nicholas - Poster 121

Siegelbaum, Robert H - Poster 94,

Paper 22

Poster 111 Mougenot, Charles - Paper 22 Moussa, Marwan - Poster 60

Poster 117

Rubinsky, Boris - Paper 3, Paper 42

Poster 105, Poster 117, Poster 131

Poster 97, Poster 132 Singh, Abhijeet - Poster 32

Moustafa, Amr Soliman - Poster 35

Patel, Shyam - Poster 118

Muallem, Nadim - Poster 27

Patel, Tanay - Poster 44

Mukunda, Geetha Jagadesh - Poster 131

Patil, Sushil - Poster 95

Murata, Shinichi - Poster 53

Pellegrin, Amelie - Poster 135

Saad, Wael A - Poster 54

Smetts, Matthew - Poster 67

Murthy, Ravi - Poster 79

Peng, Zhenwei - Paper 28, Paper 29,

Sabbah, Nathaniel - Poster 72

Smirniotopoulos, John - Poster 141

Sabir, Sharjeel H - Paper 38, Poster 13,

Smolka, Susanne - Paper 8, Paper 25,

Poster 62, Poster 63, Poster 64

N

Petre, Elena Nadia - Poster 94, Poster 132, Poster 136, Poster 146

Nadolski, Gregory - Poster 41, Poster 43, Poster 56 Nakada, Stephen - Poster 14 Narayanan, Harish - Poster 144

S

Small, William C - Poster 15

Poster 76 Saccomandi, Paola - Paper 43

Picado Roque, Omar A - Paper 26

Saddekni, Souheil - Poster 35

Piemonte, Thomas - Poster 12

Sahu, Sonia - Paper 25, Paper 11,

Pierredon, Marie-Ange - Paper 36, Poster 2

Singh, Ayushi - Poster 49, Poster 109

Poster 90 Salaria, Safia - Paper 7

Paper 11, Paper 32, Poster 80, Poster 81, Poster 91 Smolock, Amanda - Paper 24, Poster 4, Poster 124 Sofocleous, Constantinos T - Poster 94, Poster 97, Poster 146

e114

Author Index

Solomon, Stephen B - Paper 45, Paper 19,

U

Poster 97, Poster 136, Poster 146 Sotirchos, Vlasios S - Poster 94, Poster 97

Poster 144 Ueshima, Eisuke - Paper 45

Wood, Christopher G - Poster 13

Unger, Keith - Poster 68, Poster 92

Woodrum, David A - Poster 96

Soulen, Michael C - Paper 34, Paper 37,

Woods, Michael - Poster 121

Poster 41, Poster 43, Poster 56

V

Spiliopoulos, Stavros - Poster 3 Srimathveeravalli, Govindarajan - Paper 45, Paper 19, Poster 136 Stashek, Kristen - Paper 34

Vallapureddy, Vineel - Poster 137

Paper 22

X

Steadman, Brent T - Poster 42

van Houten, Diana - Paper 37

Stehling, Michael Klaus - Paper 3,

Van Tine, Brian A - Poster 111 Vannucchi, Letizia - Poster 130

Poster 88

Varano, Gianluca Maria - Paper 35 Varma, Rakesh - Poster 145

Stewart, Samantha - Paper 13 Stolka, Philipp J - Poster 28

Vasanthraj, Praveen Kumar Poster 105 Vavricek, Joseph - Poster 48

Sun, Lingyi - Poster 5

Venkat, Shree - Paper 26

Sun, Zhichao - Paper 17

Vetter, John - Poster 121

Sze, Daniel Yung-Ho - Paper 34,

Viana, Publio Cesar Cavalcante Poster 23

T

Xiao, Yue Yong - Poster 19, Poster 20, Poster 21, Poster 26, Poster 29, Poster 30 Xie, Xiaoyan - Poster 36, Poster 37, Poster 75, Poster 103 Xing, Minzhi - Paper 31, Poster 73, Poster 102, Poster 127

Streitparth, Florian - Paper 5

Poster 40

Wu, Zheng-yang - Poster 38

van Breugel, Johanna MM - Paper 20,

van Hasselt, CA - Poster 123

Stewart, Kevan - Poster 25, Poster 87,

Worakitsitisatorn, Akeanong Poster 31

Stavropoulos, S William - Paper 37

Paper 42

Wood, Bradford J - Poster 28, Poster 78,

Xu, Sheng - Poster 28, Poster 78

Y Yakoub, Danny - Paper 26

Violari, Elena G - Poster 97

Yamaguchi, Hisashi - Poster 53

Vlantis, AC - Poster 123

Yamaura, Hidekazu - Poster 53 Yan, Fei - Paper 1

Talamo, Maria - Poster 39

W

Poster 74 Tam, Alda L - Paper 38, Poster 79 Tanpowpong, Natthaporn - Poster 71 Tarantino, Luciano - Paper 27, Poster 39,

Wainstejn, David - Poster 91 Wallace, Adam Nathan - Paper 12, Poster 111 Wallace, Michael J - Poster 79

Poster 45, Poster 46, Poster 47,

Walsh, Edward - Paper 41, Poster 24

Poster 106

Wang, Li Juan - Poster 9

Tarantino, Paolo - Paper 27, Poster 39, Poster 45, Poster 46, Poster 47

Yan, Kun - Paper 1, Paper 2 Yang, Wei - Paper 1, Paper 2

Talenfeld, Adam D - Paper 4, Paper 30,

Yarmohammadi, Hooman - Paper 34, Poster 94, Poster 97 Yim, Douglas - Poster 110 Young, Charles - Poster 67

Z

Wang, Sangsang - Poster 123 Wang, Song - Paper 1, Paper 2

Zachman, Andrew - Poster 137

Tatli, Servet - Poster 33

Ward, Thomas - Poster 65

Zampino, Maria Giulia - Paper 35

Tegel, Bruno Rembert - Paper 9

Watts, Micah - Poster 109

Zanini, Maria - Poster 77

Teitelbaum, Ursina M - Paper 37

Wei, Yingtian - Poster 26, Poster 29,

Zapf, Stefan - Paper 3

Thai, Janice - Poster 28, Poster 144

Poster 30

Thyss, Antoine - Poster 135

Weisbrod, Adam J - Poster 83, Poster 96

Timmerman, Robert D - Poster 111

Wells, Shane A - Paper 6, Poster 14,

Zechlinski, Joseph John - Poster 11, Poster 122 Zeng, Dexing - Poster 5

Tmanova, Lyubov - Poster 58

Poster 16, Poster 17, Poster 124,

Zhang, Jianhao - Poster 114

Tohma, Takeyuki - Poster 86

Poster 128

Zhang, Xiaobo - Poster 21

Tong, Michael CF - Poster 123

White, Sarah B - Paper 18, Paper 39,

Zhang, Yachao - Poster 52

Tosoratti, Nevio - Poster 143

Paper 33, Paper 34, Paper 10,

Zhao, Jing - Poster 147

Tran, Nam D - Poster 111

Poster 11, Poster 59, Poster 82

Zhao, Yan - Paper 25, Paper 11,

Treilhard, John - Paper 8, Paper 11, Paper 32, Poster 80, Poster 81

Whitmore, Morgan - Poster 110

Poster 90

Wick, Jo - Poster 48

Zheng, Hai-Rong - Paper 1

Tsang Mui Chung, Michelle - Poster 9

Wieners, Gero - Paper 5

Zheng, Jiasheng - Poster 138

Tselikas, Lambros - Paper 40

Wildenberg, Joe - Poster 43

Zhong, Xiaodong - Poster 82

Turkbey, Baris - Poster 78

Willatt, Jonathon M.G - Poster 54

Ziemlewicz, Timothy - Paper 6,

Turnquist, Alyssa - Paper 15

Wittman, Tyler - Poster 14

Tutton, Sean - Paper 39, Poster 11,

Wong, Ching-yee O - Poster 116

Poster 59, Poster 122

Wong, Vincenzo - Poster 17

Poster 16, Poster 17, Poster 57, Poster 124, Poster 128 Ziv, Etay - Poster 94