- Email: [email protected]
Risk Factors for Recurrence in Childhood and Adolescent Thyroid Cancer
Abstracts / Brachytherapy 12 (2013) S11eS77 of cancer or their serum creatinine was O1.5 mg/dL. Rectal, bladder, and prostate doses were calculated based upon treatment planning computed tomography scans. The Mann-Whitney U test with an alpha (type I) error 5 0.05 was used to compare two independent samples of observations. Results: The mean prostate size in the gel group was 54 cc vs. 53 cc in the no gel group. Gel increased the separation between the prostate and rectum by 5 to 19 mm. The mean rectal V75 was 0.09 cc and 0.32 cc with and without gel, respectively (p!0.001), and the mean rectal D2cc was 48% and 58% with and without gel, respectively (p!0.001). The mean rectal D2cc was 51% and 45% in the first 25 patients and the second 25 patients treated with gel, respectively (p50.01). The mean bladder V75 was 0.52 cc and 0.62 cc with and without gel, respectively (p50.32), and the mean bladder D2cc was 59% and 63% with and without gel, respectively (p50.09). Mean prostate D90 and V100 were 104% and 94% with gel and 105% and 95% without gel (p50.20 and p50.28, respectively). There was no acute toxicity attributable to injection of the gel. Conclusions: Use of a gel to temporarily displace the rectum away from the prostate leads to a significant reduction in radiation dose delivered to the anterior rectal wall and no significant change in radiation dose delivered to the bladder. There is a learning curve to gel injection, with an increased reduction in rectal dose as one gains experience. Dosimetric coverage of the prostate was not affected by use of the gel.
POSTER DISCUSSION: MISCELLANEOUS Thursday, April 18, 2013 9:00 AMe10:00 AM PD01 Advantages of Image-Guidance in Locally Advanced Anal Cancer HDR Brachytherapy Vladymir A. Solodky, Corresponding Member, Vera A. Titova, Professor, Julya M. Kreynina, DS, Vladimir Y. Petrovsky, PhD, Anna N. Shipilova, PhD. Brachytherapy, Russian Scientific Center of Roentgenoradiology, Moscow, Russian Federation. Purpose: Anal function preservation and no colostomy are the very important issues for patients with locally advanced anal cancer (LACC). One consider chemoradiation with interstitial brachy as a boost technique a preferable way of anal cancer conservative treatment, but the implantation difficulties and complications limit the treatment access. We evaluated the capabilities of new advanced technique e MR-based imageeguided brachytherapy (IGBT) with 9-channel flexible MRcomparable cylindric applicator e in multimodal treatment of LACC. Materials and Methods: Sixty-nine patients, (32 men and 37 women, 3779 y.o.) were treated conservatively because of morphologically verified anal cancer T2-4No-2Mo with external sphincter involvement in 23 (33.3%) pts. 60Co (48 pts.) and 192Ir (21 pts.) HDR intracavitary brachytherapy was performed after chemoradiation (PFu, TP) and EBRT TD 46-50Gy to whole pelvis in 2Gy per fraction. In LN-positive patients groin lymph nodes were irradiated additionally till TD 60Gy. MRI 1,5Tl, abdominal and transrectal ultrasound were used for tumor monitoring, control of insertion and planning of brachytherapeutic applications. We used oneechannel hard cylindrical applicator, standard planning, for 60 Co, and MR-comparable 9-channel flexible plastic mould (NucletronÒ) with MR-based individualized 3D dose optimization, for 192Ir intra anal applications. For 192Ir IGBT group primary tumor extension with minimal safety margins 10mm for normal mucosa and skin was defined as CTV, 2.4 e 8.2cc [mean 4.6cc], with 2-5.5cm of tumor proximal extension from anal margin. We prescribe 2Gy to the surface of intact anal mucosa and 3.6 - 4Gy to D90 of CTV per day. TD for brachy boost was 12-16Gy in intact anal mucosa and 21-24Gy in residual tumor or tumor bed, with TD of combined irradiation 67- 74Gy for CTV. Results: We reached complete response (CR) in 33 (47.8%) pts., partial (PR) O75% in 13 (18.8%), with significant results improvement in 192Ir vs 60Co group: CR e 14 (67%) vs 19 (39.6%), PR e 5 (23,8%) vs 8 (16.7%). In 36-mo overall survival (OS) was 50.75.1%, disease-free survival (DFS) 39.17.6%. Intergroup comparison: OS 61.93.8% vs
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45.82.8% (p! 0.05), DFS 52.44.7% vs 33.32.9% (p!0.1) in Ir vs 60 Co group, respectively. No acute complications Grade IV were registered. Conclusions: MR-based 3Deoptimized 192Ir IGBT can be considered a method of choice for sphincter preserved treatment of locally advanced anal cancer.
PD02 Non-Melanoma Skin Cancer Treated with Electronic Brachytherapy: Results at One Year Ajay Bhatnagar, MD, MBA1,2. 1Cancer Treatment Services e Arizona, Casa Grande, AZ; 2Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA. Purpose: We report clinical outcomes at one year or more following highdose-rate (HDR) electronic brachytherapy (EBT) using surface applicators for treatment of non-melanoma skin cancer (NMSC). Materials and Methods: From July 2009 to April 2012, 122 patients with 171 NMSC lesions were treated with EBT to a dose of 40.0 Gy in 8 fractions, delivered twice weekly. At followup, patients were assessed for acute and late toxicities, cosmesis and local control. Results: Treatment of 171 lesions was completed in 122 patients with a mean age 73 years. There have been no recurrences to date with a mean followup of 10 months (range 1-28 months). One year or longer followup data was available for 46 lesions in 42 patients. Hypopigmentation (all grade1) was present in 5 (10.9%) of 46 lesions at one year. Other late effects at one year included dry desquamation, alopecia and rash dermatitis which occurred in 1 (2.2%), 1 (2.2%), and 3 (6.5%) of 46 lesions, respectively. No grade 3 or higher adverse events were observed at any time point. Cosmesis was evaluated at one year for 42 of 46 lesions and was excellent for 39 (92.9%) and good for 3 (7.1%) of the 42 evaluable lesions. Conclusions: Treatment of NMSC with HDR EBT using surface applicators was effective with no recurrences, good to excellent cosmesis and acceptable toxicities at one year or more post-treatment. HDR EBT provides a convenient non-surgical treatment option for NMSC patients.
PD03 Risk Factors for Recurrence in Childhood and Adolescent Thyroid Cancer Stephanie Markovina, MD, PhD, Todd A. DeWees, PhD, Perry W. Grigsby, MD. Radiation Oncology, Washington University School of Medicine, St. Louis, MO. Purpose: Appropriate management of differentiated thyroid cancer in pediatric patients is not well established. In this study we evaluated the correlation of clinical and treatment factors on disease control and survival in pediatric patients with well-differentiated thyroid cancer (DTC). We also explored patterns of recurrence and surveillance approaches. Materials and Methods: We reviewed a prospectively collected cohort of 113 patients with DTC treated at our institution, ranging in age from 4.2 to 21.9 years. One hundred two patients (90%) were treated with upfront total thyroidectomy, while 3 patients received subtotal thyroidectomy and 9 patients received lobectomy. All but 21 patients received post-operative radioactive iodine, and all patients subsequently received hormone replacement/suppressive therapy. Patients were followed with clinical exams, serum thyroid stimulating hormone (TSH) levels, and whole body 131 I scintigraphy. Results: The cohort consisted of 24 males and 89 females, the majority of which were Caucasian (101 patients). Tumor histology was largely papillary (77%), and at the time of diagnosis, only 40 patients (35%) had disease confined to the thyroid. The overall survival rate with a mean followup of 18.9 years (median 17.4) in our cohort was 98%. 10-year progression-free survival was 72%, with 40 patients (35%) experiencing recurrence by time of analysis. The mean time to first recurrence was 8.3 years (range 0 to 36). Not receiving post-operative 131I was significantly associated with recurrence (p 5 0.0038). The cumulative recurrence-free survival of
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Abstracts / Brachytherapy 12 (2013) S11eS77 131
patients with one negative whole body I scan was 75%, compared to 100% for patients with 3 or more consecutive negative scans. Conclusions: Prognosis for DTC depends heavily on age. Compared to those diagnosed in adulthood, patients diagnosed in the first two decades of life have a low-risk of mortality, but more extensive disease at diagnosis and significantly higher recurrence rates. Total thyroidectomy followed by post-operative 131I is associated with the lowest risk of recurrence. We found that three consecutive negative total body 131I scans has a strong negative predictive value for recurrence.
than 5% for point A dose, D90 and D100 of the GTVB, and D2cc in the bladder and rectum, with no significant changes greater than 10%.
PD04
Purpose: Brachytherapy (BT) can be used to deliver highly conformal treatments in the head and neck. Interstitial implants or intracavitary molds can be used in the oral cavity and oropharynx, but are timeconsuming and operator dependent. A supraglottic airway is a device that fits into the upper airway and is secured with an inflatable cuff. It is often used as a quick and operator-independent alternative to endotracheal intubation. We present a virtual model of a an endocavitary BT applicator based on such a device, and illustrate its use by comparing BT and intensity modulated radiation therapy (IMRT) treatment plans for the same supraglottic tumor. Materials and Methods: After Human Subjects Committee approval, an archived computed tomography (CT) scan was obtained of a patient with a supraglottic airway device in place. The patient’s normal structures and the airway device were contoured using Oncentra (Nucletron) software and four virtual catheters were embedded in the device. A dummy 1cc gross tumor volume (GTV) was placed in the left arytenoid and a clinical target volume (CTV) expansion of 5mm was performed, respecting anatomic boundaries. For BT, the planning target volume (PTV) 5 CTV. For IMRT, PTV 5 CTV þ 5 mm. A high-dose-rate (HDR) BT plan was produced in Oncentra using manual catheter loading and graphic
Evaluation of Tandem Localization Errors on MRI-Based Cervix Cancer Brachytherapy Lindsey Sinovic, BS, Baozhou Sun, PhD, Todd DeWees, PhD, Pawel Dyk, MD, Jose Garcia-Ramirez, MS, Perry Grigsby, MS, Jacqueline Esthappan, PhD. Radiation Oncology, Washington University School of Medicine, St. Louis, MO. Purpose: For magnetic resonance (MR)-based high-dose-rate (HDR) cervix cancer brachytherapy, susceptibility artifacts in the images can distort the boundaries of the titanium tandem, impeding localization of the tandem in the images, and adversely affecting the determination of source dwell positions. Here, we examined how inaccurate determination of the tandem tip, and of the source positions based relative to this tip, affects the dose delivered to the tumor and normal tissue volumes. Materials and Methods: Twenty patients were implanted with a titanium tandem and colpostat applicator and imaged on a 1.5-T MR scanner at time of brachytherapy. Images were imported into a brachytherapy treatment planning system. The gross tumor volume (GTVB), bladder, rectum, and sigmoid were delineated manually, followed by localization of the applicator. Forward treatment planning was performed using standard source distribution rules normalized to point A, with no optimization of dose to target or normal structures. Only standard 6 cm tandem length was considered, which led to three groups of three activated dwells separated by a 0.5 cm gap. The plan for each patient was copied and then altered by shifting the train of dwell positions in the tandem by 0.1 cm increments along the tandem. Ten shifts in total were made (five shifts inferior and five shifts superior relative to the original dwell positions) resulting in ten separate isodose plans per patient. These ten shifted isodose distributions were individually compared to the original isodose distribution in terms of mean absolute percent differences in the following plan metrics: dose to point A, dose delivered to 90% and 100% (D90 and D100) of the GTVB, and the minimum dose delivered to 2 cm3 of irradiated tissue volume (D2cc)in the bladder, rectum, and sigmoid. All doses were expressed in equivalent doses in 2 Gy fractions by use of the linear-quadratic model (a/b 5 3Gy). For each metric, t-tests were performed to determine which shifts, if any, resulted in statistically significant mean absolute differences greater than thresholds of 5% and 10%. Paired t-tests were performed to determine if the mean absolute differences had a directional dependence on shift, i.e., superior versus inferior. Results: A shift was deemed to cause a significant change in the metric greater than the threshold if the p-value was less than 0.05. At the 5% threshold, the mean absolute difference in bladder D2cc was significant at shifts greater than 0.2 cm, followed by D90 and point A dose (shiftsO0.3 cm), and then with the D100 and the D2cc to rectum and sigmoid (shifts$0.5 cm). Mean absolute differences greater than 10% were not statistically significant for any of the metrics or shifts studied here. Significant differences (p!0.05) between equidistant superior and inferior shifts were observed for dose to point A, rectum D2cc, and D90 with shifts greater than 0.1 cm, followed by bladder D2cc (shiftsO0.2 cm) and sigmoid D2cc (shiftsO0.3 cm). There were no significant differences based on direction of shift for theD100. Conclusions: Tandem localization errors in the range of 0.1e0.5 cm were simulated for tandem and colpostat cervix HDR brachytherapy plans, generated using standard source distribution rules and no optimization. Significant changes were observed in mean absolute differences greater
PD05 A Novel Endocavitary HDR Brachytherapy Applicator for Treatment of the Deep Oropharynx, Posterior Pharyngeal Wall, Supraglottic Larynx, and Hypopharynx Benjamin D. Weinberg, MD, MA, Hongyu Jiang, PhD, Nathan Aguilera, MS, CMD, Christopher E. Lominska, MD. Radiation Oncology, University of Kansas Medical Center, Kansas City, KS.
POSTER DISCUSSION: MISCELLANEOUS Thursday, April 18, 2013 9:00 AMe10:00 AM PD01 Advantages of Image-Guidance in Locally Advanced Anal Cancer HDR Brachytherapy Vladymir A. Solodky, Corresponding Member, Vera A. Titova, Professor, Julya M. Kreynina, DS, Vladimir Y. Petrovsky, PhD, Anna N. Shipilova, PhD. Brachytherapy, Russian Scientific Center of Roentgenoradiology, Moscow, Russian Federation. Purpose: Anal function preservation and no colostomy are the very important issues for patients with locally advanced anal cancer (LACC). One consider chemoradiation with interstitial brachy as a boost technique a preferable way of anal cancer conservative treatment, but the implantation difficulties and complications limit the treatment access. We evaluated the capabilities of new advanced technique e MR-based imageeguided brachytherapy (IGBT) with 9-channel flexible MRcomparable cylindric applicator e in multimodal treatment of LACC. Materials and Methods: Sixty-nine patients, (32 men and 37 women, 3779 y.o.) were treated conservatively because of morphologically verified anal cancer T2-4No-2Mo with external sphincter involvement in 23 (33.3%) pts. 60Co (48 pts.) and 192Ir (21 pts.) HDR intracavitary brachytherapy was performed after chemoradiation (PFu, TP) and EBRT TD 46-50Gy to whole pelvis in 2Gy per fraction. In LN-positive patients groin lymph nodes were irradiated additionally till TD 60Gy. MRI 1,5Tl, abdominal and transrectal ultrasound were used for tumor monitoring, control of insertion and planning of brachytherapeutic applications. We used oneechannel hard cylindrical applicator, standard planning, for 60 Co, and MR-comparable 9-channel flexible plastic mould (NucletronÒ) with MR-based individualized 3D dose optimization, for 192Ir intra anal applications. For 192Ir IGBT group primary tumor extension with minimal safety margins 10mm for normal mucosa and skin was defined as CTV, 2.4 e 8.2cc [mean 4.6cc], with 2-5.5cm of tumor proximal extension from anal margin. We prescribe 2Gy to the surface of intact anal mucosa and 3.6 - 4Gy to D90 of CTV per day. TD for brachy boost was 12-16Gy in intact anal mucosa and 21-24Gy in residual tumor or tumor bed, with TD of combined irradiation 67- 74Gy for CTV. Results: We reached complete response (CR) in 33 (47.8%) pts., partial (PR) O75% in 13 (18.8%), with significant results improvement in 192Ir vs 60Co group: CR e 14 (67%) vs 19 (39.6%), PR e 5 (23,8%) vs 8 (16.7%). In 36-mo overall survival (OS) was 50.75.1%, disease-free survival (DFS) 39.17.6%. Intergroup comparison: OS 61.93.8% vs
S35 192
45.82.8% (p! 0.05), DFS 52.44.7% vs 33.32.9% (p!0.1) in Ir vs 60 Co group, respectively. No acute complications Grade IV were registered. Conclusions: MR-based 3Deoptimized 192Ir IGBT can be considered a method of choice for sphincter preserved treatment of locally advanced anal cancer.
PD02 Non-Melanoma Skin Cancer Treated with Electronic Brachytherapy: Results at One Year Ajay Bhatnagar, MD, MBA1,2. 1Cancer Treatment Services e Arizona, Casa Grande, AZ; 2Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA. Purpose: We report clinical outcomes at one year or more following highdose-rate (HDR) electronic brachytherapy (EBT) using surface applicators for treatment of non-melanoma skin cancer (NMSC). Materials and Methods: From July 2009 to April 2012, 122 patients with 171 NMSC lesions were treated with EBT to a dose of 40.0 Gy in 8 fractions, delivered twice weekly. At followup, patients were assessed for acute and late toxicities, cosmesis and local control. Results: Treatment of 171 lesions was completed in 122 patients with a mean age 73 years. There have been no recurrences to date with a mean followup of 10 months (range 1-28 months). One year or longer followup data was available for 46 lesions in 42 patients. Hypopigmentation (all grade1) was present in 5 (10.9%) of 46 lesions at one year. Other late effects at one year included dry desquamation, alopecia and rash dermatitis which occurred in 1 (2.2%), 1 (2.2%), and 3 (6.5%) of 46 lesions, respectively. No grade 3 or higher adverse events were observed at any time point. Cosmesis was evaluated at one year for 42 of 46 lesions and was excellent for 39 (92.9%) and good for 3 (7.1%) of the 42 evaluable lesions. Conclusions: Treatment of NMSC with HDR EBT using surface applicators was effective with no recurrences, good to excellent cosmesis and acceptable toxicities at one year or more post-treatment. HDR EBT provides a convenient non-surgical treatment option for NMSC patients.
PD03 Risk Factors for Recurrence in Childhood and Adolescent Thyroid Cancer Stephanie Markovina, MD, PhD, Todd A. DeWees, PhD, Perry W. Grigsby, MD. Radiation Oncology, Washington University School of Medicine, St. Louis, MO. Purpose: Appropriate management of differentiated thyroid cancer in pediatric patients is not well established. In this study we evaluated the correlation of clinical and treatment factors on disease control and survival in pediatric patients with well-differentiated thyroid cancer (DTC). We also explored patterns of recurrence and surveillance approaches. Materials and Methods: We reviewed a prospectively collected cohort of 113 patients with DTC treated at our institution, ranging in age from 4.2 to 21.9 years. One hundred two patients (90%) were treated with upfront total thyroidectomy, while 3 patients received subtotal thyroidectomy and 9 patients received lobectomy. All but 21 patients received post-operative radioactive iodine, and all patients subsequently received hormone replacement/suppressive therapy. Patients were followed with clinical exams, serum thyroid stimulating hormone (TSH) levels, and whole body 131 I scintigraphy. Results: The cohort consisted of 24 males and 89 females, the majority of which were Caucasian (101 patients). Tumor histology was largely papillary (77%), and at the time of diagnosis, only 40 patients (35%) had disease confined to the thyroid. The overall survival rate with a mean followup of 18.9 years (median 17.4) in our cohort was 98%. 10-year progression-free survival was 72%, with 40 patients (35%) experiencing recurrence by time of analysis. The mean time to first recurrence was 8.3 years (range 0 to 36). Not receiving post-operative 131I was significantly associated with recurrence (p 5 0.0038). The cumulative recurrence-free survival of
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Abstracts / Brachytherapy 12 (2013) S11eS77 131
patients with one negative whole body I scan was 75%, compared to 100% for patients with 3 or more consecutive negative scans. Conclusions: Prognosis for DTC depends heavily on age. Compared to those diagnosed in adulthood, patients diagnosed in the first two decades of life have a low-risk of mortality, but more extensive disease at diagnosis and significantly higher recurrence rates. Total thyroidectomy followed by post-operative 131I is associated with the lowest risk of recurrence. We found that three consecutive negative total body 131I scans has a strong negative predictive value for recurrence.
than 5% for point A dose, D90 and D100 of the GTVB, and D2cc in the bladder and rectum, with no significant changes greater than 10%.
PD04
Purpose: Brachytherapy (BT) can be used to deliver highly conformal treatments in the head and neck. Interstitial implants or intracavitary molds can be used in the oral cavity and oropharynx, but are timeconsuming and operator dependent. A supraglottic airway is a device that fits into the upper airway and is secured with an inflatable cuff. It is often used as a quick and operator-independent alternative to endotracheal intubation. We present a virtual model of a an endocavitary BT applicator based on such a device, and illustrate its use by comparing BT and intensity modulated radiation therapy (IMRT) treatment plans for the same supraglottic tumor. Materials and Methods: After Human Subjects Committee approval, an archived computed tomography (CT) scan was obtained of a patient with a supraglottic airway device in place. The patient’s normal structures and the airway device were contoured using Oncentra (Nucletron) software and four virtual catheters were embedded in the device. A dummy 1cc gross tumor volume (GTV) was placed in the left arytenoid and a clinical target volume (CTV) expansion of 5mm was performed, respecting anatomic boundaries. For BT, the planning target volume (PTV) 5 CTV. For IMRT, PTV 5 CTV þ 5 mm. A high-dose-rate (HDR) BT plan was produced in Oncentra using manual catheter loading and graphic
Evaluation of Tandem Localization Errors on MRI-Based Cervix Cancer Brachytherapy Lindsey Sinovic, BS, Baozhou Sun, PhD, Todd DeWees, PhD, Pawel Dyk, MD, Jose Garcia-Ramirez, MS, Perry Grigsby, MS, Jacqueline Esthappan, PhD. Radiation Oncology, Washington University School of Medicine, St. Louis, MO. Purpose: For magnetic resonance (MR)-based high-dose-rate (HDR) cervix cancer brachytherapy, susceptibility artifacts in the images can distort the boundaries of the titanium tandem, impeding localization of the tandem in the images, and adversely affecting the determination of source dwell positions. Here, we examined how inaccurate determination of the tandem tip, and of the source positions based relative to this tip, affects the dose delivered to the tumor and normal tissue volumes. Materials and Methods: Twenty patients were implanted with a titanium tandem and colpostat applicator and imaged on a 1.5-T MR scanner at time of brachytherapy. Images were imported into a brachytherapy treatment planning system. The gross tumor volume (GTVB), bladder, rectum, and sigmoid were delineated manually, followed by localization of the applicator. Forward treatment planning was performed using standard source distribution rules normalized to point A, with no optimization of dose to target or normal structures. Only standard 6 cm tandem length was considered, which led to three groups of three activated dwells separated by a 0.5 cm gap. The plan for each patient was copied and then altered by shifting the train of dwell positions in the tandem by 0.1 cm increments along the tandem. Ten shifts in total were made (five shifts inferior and five shifts superior relative to the original dwell positions) resulting in ten separate isodose plans per patient. These ten shifted isodose distributions were individually compared to the original isodose distribution in terms of mean absolute percent differences in the following plan metrics: dose to point A, dose delivered to 90% and 100% (D90 and D100) of the GTVB, and the minimum dose delivered to 2 cm3 of irradiated tissue volume (D2cc)in the bladder, rectum, and sigmoid. All doses were expressed in equivalent doses in 2 Gy fractions by use of the linear-quadratic model (a/b 5 3Gy). For each metric, t-tests were performed to determine which shifts, if any, resulted in statistically significant mean absolute differences greater than thresholds of 5% and 10%. Paired t-tests were performed to determine if the mean absolute differences had a directional dependence on shift, i.e., superior versus inferior. Results: A shift was deemed to cause a significant change in the metric greater than the threshold if the p-value was less than 0.05. At the 5% threshold, the mean absolute difference in bladder D2cc was significant at shifts greater than 0.2 cm, followed by D90 and point A dose (shiftsO0.3 cm), and then with the D100 and the D2cc to rectum and sigmoid (shifts$0.5 cm). Mean absolute differences greater than 10% were not statistically significant for any of the metrics or shifts studied here. Significant differences (p!0.05) between equidistant superior and inferior shifts were observed for dose to point A, rectum D2cc, and D90 with shifts greater than 0.1 cm, followed by bladder D2cc (shiftsO0.2 cm) and sigmoid D2cc (shiftsO0.3 cm). There were no significant differences based on direction of shift for theD100. Conclusions: Tandem localization errors in the range of 0.1e0.5 cm were simulated for tandem and colpostat cervix HDR brachytherapy plans, generated using standard source distribution rules and no optimization. Significant changes were observed in mean absolute differences greater
PD05 A Novel Endocavitary HDR Brachytherapy Applicator for Treatment of the Deep Oropharynx, Posterior Pharyngeal Wall, Supraglottic Larynx, and Hypopharynx Benjamin D. Weinberg, MD, MA, Hongyu Jiang, PhD, Nathan Aguilera, MS, CMD, Christopher E. Lominska, MD. Radiation Oncology, University of Kansas Medical Center, Kansas City, KS.