Local Management for Sarcoma Liver Metastases

Poster Viewing Session E633

Volume 93  Number 3S  Supplement 2015 on tumor location, margins, and comorbidities, noninvasive modalities such as radiation may be preferred. Historically, superficial x-rays were most commonly used to treat NMSC. Recently, the use of hypofractionated HDR brachytherapy has increased, likely due to easier treatment setup and fewer treatments. We use a modern version of brachytherapy, the ‘3D topographic applicator brachytherapy’ (3TAB) to treat NMSC since 2010. This study compares local control, toxicities, and number of treatments of x-rays vs 3TAB at our institution using matched pair analysis. Materials/Methods: 59 consecutive early stage NMSC lesions were treated with x-rays from 1999-2010 and were matched with respect to age, stage, histology, and site to 59 lesions in the 3TAB group selected from 252 lesions treated between 2010 to 2013. The x-ray group was treated with 100 kVp to a dose 40-54 Gy/10-20 fxs, based on size and depth of lesion. For 3TAB, a custom applicator was made using thermoplastic mold with HAM or Freiburg flap. A 3D optimized plan to 3 mm depth was created to deliver 40 Gy in 8 fxs, 2/wk over 4 weeks. Acute toxicity was graded by RTOG criteria for 3TAB, and for x-rays; grading was based on interpretation of follow-up notes. Chronic toxicity was graded by the presence or lack of toxicity. Cohorts were compared using Chi-square and Wilcoxon signed-rank test. Results: Outlined in Table 1. No significant difference was seen in local control and chronic toxicity between the x-ray and the 3TAB cohorts. However, there was a significant difference in acute toxicity (P <0.0001) and number of treatments, with 3TAB having less acute toxicity and fewer fractions. At the completion of treatment, 22 (37.3%) lesions in the x-ray group and 2 (3.4%) lesions in the 3TAB group had G3 dermatitis, requiring a 2-week break for 3 (5.1%) lesions in the x-ray group, and 0 (0%) in the 3TAB group. In 3TAB group, 2 (3.3%) lesions received 7/8 planned treatments. For majority of lesions in both groups, acute toxicity subsided within 3 months. Conclusion: In this study, 3TAB offers similar local control and chronic toxicity with fewer treatments and less acute toxicity thus potentially promising to be a better modality. Poster Viewing Abstracts 3586; Table 1 Number (%) or Mean (Range) Parameters Age (yrs) Site H&N Non H&N Histology BCC SCC Bowen’s disease Stage0 I II

# of Treatments F/U (mo) Status at last F/UNED Local Recurrence Acute ToxicityG1 G2 G3

Chronic Toxicity

X-ray Group NZ59

3TAB group NZ59

76 (50-94) 50 (84.7) 9 (15.3) 35 (59.3) 20 (33.9) 4 (6.8) 4 (6.8) 42 (71.2) 13 (22.0) 17 (10-26) 34.6 Median: 24.0 59 0 17 (28.8) 20 (33.9) 22 (37.3) 13 (22.0)

80 (58-98) 50 (84.7) 9 (15.3) 35 (59.3) 20 (33.9) 4 (6.8) 4 (6.8) 42 (71.2) 13 (22.0) 8 18.9 Median: 19.3 59 0 27 (45.8) 30 (50.8) 2 (3.4) 10 (16.9)

P value NS NS NS

NS

NS <0.0001

Author Disclosure: D. Olek: None. S. Vyas: None. M.M. Gestaut: None. D. Arora: None. S.G. Jhavar: None. S. Hasan: None. N. Thawani: None. C. Ord: None. N. Deb: None. J. Smith: None. S. Mutyala: None.

Purpose/Objective(s): Aggressive treatment of sarcoma oligometastases can possibly prolong overall survival (OS) and give patients (pts) a chemotherapy-free holiday (CFH). Stereotactic body radiation therapy (SBRT) is an ablative therapy with high local control (LC), but has rarely been used for sarcoma liver metastases (SLMs). This study addresses the hypothesis that tumor control between SBRT and surgery are similar and characterizes patterns of subsequent pt management. Materials/Methods: In an IRB approved study, all hospital records were queried using diagnosis and procedure codes. We identified 30 pts who underwent local treatment to 44 SLMs from 2003-14. 22 had resection of 25 lesions, 10 had SBRT to 19 lesions, 2 had both. Response to SBRT was evaluated by RECIST criteria. LC for surgery was defined as no recurrence within 1 cm of the margin. Freedom from in-liver progression (FF-LP) was defined as no liver progression distant to the treated site. CFH was determined from time of completion of treatment to date of restarting systemic therapy. Results: For SBRT pts, median age was 63 (49-76) years, tumor size 4.1 (1.2-9.3) cm, dose 50 (32-60) Gy in 5 (3-5) fractions and follow-up 10 (1-46) mo. Histologies included 1 GIST, 5 retroperitoneal leiomyosarcoma (RP LMS), 1 uterine LMS (U LMS) and 3 other. At last imaging, 7 lesions showed stable disease, 10 partial response and 2 complete response. None progressed. For surgery pts, median age was 59 (21-71) years, tumor size 3.5 (0.6-16.1) cm, and follow-up 53 (4-120) mo. 11 pts had GIST, 5 RP LMS, 4 U LMS and 2 other. 2 marginal recurrences were noted at 15.8 and 4.7 mo. SBRT pts were significantly more likely to have other sites of disease (pZ0.02) and to be older (pZ0.04), and ECOG performance status (pZ0.06) and non-GIST histology (pZ0.08) trended worse. There was no difference in Charlson comorbidity index or tumor size. Median CFH was similar between groups (2.1 mo for surgery vs 6.5 mo for SBRT, log-rank pZ0.37). After surgery, all 11 GIST pts (50%) received adjuvant systemic therapy. 2 pts (10%) with high grade sarcoma (HGS) continued the same chemotherapy. After SBRT, 1 pt with GIST and 1 pt with HGS continued the same treatment. 1 pt with HGS was started on a new chemotherapy. Systemic therapy change in all pts was due to distant metastases. Median OS and FF-LP were significantly longer for those who had surgery (90.8 vs 34.7 mo, log-rank pZ0.005 and 41.3 vs 3.5 mo, log-rank pZ0.001, respectively). Conclusion: SBRT provides excellent LC for SLMs. For pts with limited systemic disease, good performance status and favorable histology, we have tended to favor surgical resection as it offers the potential for longterm tumor control and OS. However, SBRT, which is not invasive, can also provide long-term tumor control and a CFH. Longer follow-up and refinement of pt selection is necessary to identify who would benefit most from SBRT. Author Disclosure: L.E. Kollar: None. E. Sapir: None. T.H. Welling: Research Grant; NIH. R. Chugh: Research Grant; Novartis, Morphotek, Lilly, MabVax, Biomarin. S.M. Schuetze: Research Grant; Michigan Society of Hematology/Oncology, AB Science, Amgen, Biomed Valley Discovery, Janssen, CytRx, SARC. NCI steering committee; NCCN. T.S. Lawrence: Research Grant; NIH, State of Michigan Economic Development Corp.. Partnership; PI Squared Therapeutics. Member; NCIMSA, NIH. Chair; AACR Radiation Oncology Task Force. Editorial Board Member; The ASCO Post.. Editor; The Cancer Journal and Translational Oncology, Cancer Research and Cancer Discovery. M. Feng: Research Grant; Celgene. Honoraria; Medivation/Astellas, Genoma Dx, Nanostring, Myriad. Patent/License Fees/Copyright; PFS Genomics for Radiotype Dx. GU Translational Program chair; RTOG. Clinical Advisory subcommittee co-chair; IHE-RO. pancreatic adenocarcinoma panel member; NCCN.

3587 Local Management for Sarcoma Liver Metastases L.E. Kollar,1 E. Sapir,2 T.H. Welling,3 R. Chugh,4 S.M. Schuetze,4 T.S. Lawrence,2 and M. Feng2; 1University of Washington, Seattle, WA, 2 University of Michigan, Ann Arbor, MI, 3Department of Surgery, University of Michigan, Ann Arbor, MI, 4Department of Internal Medicine, Division of Hematology/Oncology, University of Michigan, Ann Arbor, MI

3588 Treatment of Metastatic Melanoma Using Stereotactic Body Radiosurgery A.J. Lederman, M. Loksen, T. Lowinger, V.F. Fernandes, D. Izon, and G.S. Lederman; Radiosurgery New York, New York, NY