PURPOSE: Eye plaque brachytherapy (EPBT) is the most common treatment for uveal melanoma with high local control rates of 95-100%. When local recurrences occur following EPBT, salvage options include enucleation, transpupillary thermotherapy (TTT), external beam radiation, or reirradiation with EPBT. The purpose of this study is to report our institution's experience with EPBT re-irradiation for locally recurrent uveal melanoma. METHODS AND MATERIALS: Patients were included if they were previously treated for uveal melanoma with EPBT, experienced local recurrence, and were subsequently treated at our institution with EPBT from 2016- 2020. RESULTS: A total of 5 patients with median age 68 years were included. All patients were initially treated at an outside institution (OSI) with Iodine-125 or Ruthenium-106 EPBT. Mean time between EPBT at the OSI and EPBT at our facility was 130 months (range 28-231 months). Patients were re-irradiated with Iodine-125 EPBT prescribed to 85 Gy over 168 hours. Median follow up after re-treatment at our center was 24 months. Local control among this cohort was 100%. Metastasis occurred in two patients after re-treatment, at 8 months and 7 months. At last follow up, all treated lesions were decreased in size. Four patients experienced worsening visual acuity. Four patients developed cataracts, while two patients developed radiation retinopathy with cystoid macular edema requiring anti-VEGF injections. One patient developed radiation retinopathy but did not require injections. No patients required enucleation. CONCLUSIONS: Re-treatment of locally recurrent uveal melanomas with EPBT is a feasible alternative to enucleation with a high local control rate. Ocular toxicities have not been significant enough to require enucleation. (c) 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Purpose: Nodal marginal zone lymphoma (NMZL) localized to a single lymphatic region (ie, stage I) is a relatively rare diagnosis. Current guidelines permit these patients to be either observed or treated with systemic therapy (ST), radiation therapy (RT), or both modalities. The prognostic effect of ST or RT compared with observation has not been established. The purpose of this study was to assess the prognostic effect of therapy in stage I NMZL.Methods and Materials: The National Cancer Database was queried (2004-2018) for all patients with stage I NMZL. Patients were stratified based on treatment received. Propensity score matching (PSM) was performed overall and for each disease site to create 1:1 matched cohorts of patients who received RT and those who did not. Kaplan-Meier analysis evaluated overall survival (OS). Univariable (UVA) and multivariable Cox proportional hazard analyses identified clinical and treatment factors prognostic for OS. Subset analysis excluded patients deceased within 1 month of diagnosis to account for immortal time bias.Results: A total of 3201 patients (median age 67) met inclusion criteria. A total of 1042 patients (33%) were head/neck/face, 208 (7%) intrathoracic, 613 (19%) intra-abdominal, 382 (12%) axilla/upper extremity, 292 (9%) inguinal/lower extremity, 86 (3%) pelvic, and 578 (18%) unspecified. A total of 1562 patients (49%) received no treatment, 721 (23%) received ST alone, 799 (25%) received RT alone, and 119 (4%) received both ST and RT. After PSM, ST was not prognostic on UVA while RT was prognostic on both UVA and multivariable analysis. After PSM, the 5-year OS was 84% for those who received RT and 79% for those who did not (P = .026). On subset analysis, these findings remained statistically significant for the head/neck/face cohort and the axilla/upper extremity cohort. After accounting for immortal time bias and performing PSM on this subset, the 5-year OS was 82% for those who received RT and 77% for Conclusions: In the overall cohort, RT improved OS compared with no RT, and ST was not a factor associated with OS. A radiation oncologist should be consulted for all patients with stage I NMZL for multidisciplinary decision making. (c) 2022 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

BACKGROUND:The purpose of this study is to analyze renal function outcomes in abdominal neuroblastoma patients undergoing proton therapy (PT). PROCEDURE:From 2011 to 2019, two single-institution Institutional Review Board-approved protocols prospectively enrolled neuroblastoma patients for data collection. To assess renal function, serum creatinine (Cr), blood urea nitrogen (BUN), and creatinine clearance (CrCl) before proton therapy (pre-PT) were compared with the values at last follow-up. RESULTS:A total of 30 children with abdominal neuroblastoma with median age 3.5 years (range, 0.9-9.1) at time of PT were included in this study. All patients underwent chemotherapy and resection of primary tumor prior to PT. Two patients required radical nephrectomy. Median follow-up after PT was 35 months. Mean dose to ipsilateral and contralateral kidney was 13.9 and 5.4 Gy, respectively. No patients developed hypertension or renal dysfunction during follow-up. There was no statistically significant change in serum BUN (p = .508), CrCl (p = .280), or eGFR (p = .246) between pre-PT and last follow-up. CONCLUSION:At a median follow-up of almost 3 years, renal toxicity was uncommon after PT. Longer follow-up and larger patient cohort data are needed to further assess impact of PT on renal function in this population.

Purpose Unresectable cholangiocarcinoma is managed with any combination of systemic therapy and local therapies such as radiotherapy (RT). The purpose of this study is to use a large national database to assess the utilization rate and prognostic impact of brachytherapy (BT) in this setting. Materials and Methods The National Cancer Database (NCDB) was queried (2004-2017) for patients with unresected cholangiocarcinoma. Pearson chi-square testing was used to compare categorical frequencies between patients who received external beam RT without BT (EBRT alone) and patients who received BT. Propensity score matching (PSM) was performed to create a 1:1 matched cohort of patients who received EBRT alone v. BT. Kaplan-Meier analysis was used to evaluate overall survival (OS). Univariate (UVA) and multivariate (MVA) analyses were conducted using Cox proportional hazard models to determine which demographic and clinical factors were prognostic for OS. Results A total of 40,187 patients with median age 69 (IQR 60- 78) were included in this study. A total of 15,089 (37.5%) were extrahepatic cholangiocarcinoma and 25,098 (62.5%) were intrahepatic cholangiocarcinoma. A total of 19,397 (49.8%) received chemotherapy (CTX) while 19,589 (50.2%) did not. A total of 35,023 (87.2%) received no RT, 4,234 (10.5%) received EBRT alone, and 930 (2.3%) received BT. EBRT doses ranged from palliative doses of 20 Gy to definitive doses of 60 Gy (median 45Gy, IQR 30- 50.4). BT doses were not available in >90% of cases. Compared to EBRT alone, patients who received BT were more likely diagnosed in 2013 or later (p< 0.001), more likely white race (p= 0.049), more likely treated at an academic center (p < 0.001), more likely insured (p< 0.001), more likely to travel farther to treatment center (p< 0.001), more likely to have intrahepatic disease (p< 0.001), more likely to have earlier stage disease (p< 0.001), and less likely to receive chemotherapy (p< 0.001). After PSM, there were no differences in demographic or clinical factors between patients who received EBRT alone v. BT. After PSM, the median OS was 9.2 months for EBRT alone and 14.7 months for BT (p< 0.001). On UVA after PSM, BT (HR 0.637, p< 0.001; 95% CI 0.560- 0.725), CTX (HR 0.844, p=0.11; 95% CI 0.741- 0.962), female sex (HR 0.841, p=0.008; 95% CI 0.739- 0.956), academic facility (HR 0.804, p=0.001; 95% CI 0.707- 0.914), and further distance from treatment center (HR 0.804, p=0.008; 95% CI 0.686- 0.944) were positive prognostic factor while higher stage (HR 1.814, p< 0.001; 95% CI 1.591- 2.067) was a negative prognostic factor. All prognostic factors remained significant on MVA. Conclusions The utilization rate of BT has increased and certain demographic and clinical factors are associated with its use. BT has a positive prognostic impact relative to EBRT alone and a future prospective randomized trial should be performed to confirm this.

Purpose In the management of uveal melanoma, eye plaque brachytherapy (EPBT) has replaced enucleation as the standard of care for small size tumors that require treatment, and for medium size tumors. In the modern era, EPBT is being utilized more frequently for certain large tumors as well. While there is prospective randomized evidence to support utilization of EPBT for tumors of appropriate dimensions, it is unclear what the actual practice patterns are across the United States. The purpose of this publication was to look at contemporary trends in the management of uveal melanoma across the United States to determine whether practices are appropriately adopting EPBT, and to investigate demographic and socio-economic factors that might be associated with deviations from this standard of care. Material and methods The National Cancer Database was queried (2004-2015) for patients with uveal melanoma. Data regarding tumor characteristics and treatment were collected. Two-sided Pearson χ2 test was used to compare categorical frequencies between patients who received globe preserving treatments vs. those who received enucleation. Multivariable logistic regression modeling was used to determine characteristics predictive for receiving enucleation. Results The enucleation rate for small/medium tumors (≤ 10 mm apical height and ≤ 16 mm basal diameter) decreased from 20% in 2004 to 10% in 2015. The EPBT rate for large tumors increased from 30% in 2004 to 45% in 2015. Numerous demographic and socio-economic factors were found to be associated with higher rates of enucleation. Conclusions The overall trend across the nation is a decreased enucleation rate for small/medium tumors, and an increased EPBT rate for large tumors. A fraction of patients who should be candidates for EPBT are instead receiving enucleation, and in this study, we have shown that certain adverse demographic factors are associated with this.

Purpose Hepatobiliary cancers are rare neoplasms that often present in an inoperable state. In 2020 there were an estimated, newly diagnosed 42,810 "liver and intrahepatic bile duct" cancers and 11,980 "gallbladder and other biliary" cancers. Patients often present with malignant biliary tract obstruction in the setting of locally advanced or metastatic disease and radiation is reserved for palliative reasons. In some patients who are dispositioned to liver transplant (LTX), radiation can be used as a bridging therapy. The purpose of this study was to look at our institutions experience in treating patients with a combination of external beam radiation (EBRT) and hepatobiliary brachytherapy (BT) as they await LTX. Materials and Methods Medical records were retrospectively reviewed at our institution and patients diagnosed with cholangiocarcinoma who were also treated with hepatobiliary brachytherapy were included. These patients were considered for LTX. Results Between 2019 and 2021 a total of 6 patients were treated with EBRT and BT. Median age was 69.5 (range 60-86) and median follow up was 15 months (range 3-33). 3 patients (50%) presented with nodal disease at initial workup while 0 patients were metastatic. The 3 patients with nodal disease all received chemotherapy prior to radiation with median time to RT being 10 months in these patients. In the node negative patients, median time to EBRT was 1 month after diagnosis. 5 patients underwent conventionally fractionated EBRT, 45 Gy in 25 fractions, while 1 patient underwent stereotactic body radiotherapy (SBRT), 30 Gy in 5 fractions. All patients received concurrent chemotherapy. After completion of EBRT or SBRT, all patients underwent BT, 15 Gy in 5 fractions. Afterwards, 5 patients received adjuvant maintenance chemotherapy. While on maintenance chemotherapy, 4 patients progressed to have metastatic disease. 2 patients were able to undergo LTX, 7 months and 13 months after BT. In these patients, final pathology showed that there was no viable tumor in the areas where they were treated with BT. At most recent follow up, 1 of the patients who underwent LTX was alive while the other was deceased from unknown causes. Otherwise, 2 other patients were alive but with metastatic disease, 1 was deceased, and 1 was lost to follow up but with metastatic disease. Median survival in this cohort was 19 months and overall survival was 50%. Conclusions In well selected patients whose goal is to undergo LTX, EBRT and BT can be used as a bridging therapy. Though this is a small cohort, BT did demonstrate high rates of local control in patients able to undergo LTX.

Purpose/Objectives Mucinous carcinoma (MC) of the breast is an uncommon variant of breast cancer which has a favorable prognosis. Current guidelines for ER/PR-positive, HER2-negative pure-MC state that endocrine therapy (ET) is only required for tumors ≥3cm and node-positive patients while chemotherapy (CTX) is not required but can be considered for node positive-patients. While radiation therapy (RT) currently remains a part of breast-conserving therapy (BCT) for this histology, the prognostic impact of RT in pure MC remains unclear. Materials/Methods The National Cancer Database (NCDB) was queried (2004-2017) for patients with non-metastatic, histologically confirmed MC who received breast-conserving surgery. Kaplan-Meier analysis was used to evaluate overall survival (OS). Univariate (UVA) and multivariate (MVA) analyses were conducted using Cox proportional hazard models to determine which clinical and treatment factors were prognostic for overall survival. Results A total of 24,837 patients with median age 70 (IQR 61-78) were included in this study. A total of 66% of carcinomas were grade 1 and 34% were grade 2. A total of 79% were pT1, 20% were pT2, and 1% were pT3-4. A total of 96% were pN0 and 4% were pN1-3. A total of 99% were ER+, 92% were PR+, and 96% were HER2-. A total of 61% received RT, 70% received ET, and 8% received CTX. The 10-year OS was 73% for those who received RT and 41% for those who did not. On UVA, RT (HR 0.31, p< 0.0001; CI 0.29-0.33), ET (HR 0.52, p< 0.0001; CI 0.49-0.55), CTX (HR 0.40, p< 0.0001; CI 0.35-0.46), and black race (HR 0.87, p= 0.006; CI 0.79- 0.96) were positive prognostic factors for OS while older age (HR 1.10, p< 0.0001; CI 1.09-1.10), CDCC comorbidity score (HR 1.93, p< 0.0001; CI 1.81- 2.06), and tumor size (HR 1.01, p< 0.0001; CI 1.01-1.02) were negative prognostic factors. On MVA, RT (HR 0.64, p< 0.0001; CI 0.59-0.69) and ET (HR 0.85, p< 0.0001; CI 0.78- 0.91) remained positive prognostic factors while older age (HR 1.08, p< 0.0001; CI 1.08-1.09), CDCC comorbidity score (HR 1.61, p< 0.0001; CI 1.50- 1.73), and tumor size (HR 1.02, p< 0.0001; CI 1.01- 1.02) remained negative prognostic factors; chemotherapy (HR 1.19, p= 0.039; CI 1.01- 1.39) became a negative prognostic factor and black race (HR 0.99, p= 0.92; CI 0.89- 1.12) was no longer prognostic. Conclusion This is the largest study to date on mucinous carcinoma of the breast and the role of RT after breast-conserving surgery. Use of postoperative RT after lumpectomy is associated with improved OS in patients with breast MC, suggesting that post-lumpectomy RT should remain standard of care. Citation Format: Neil Chevli, Kaidi Wang, Waqar Haque, Mary R. Schwartz, Julie Nangia, Jennifer Sasaki, Andrew M. Farach, Sandra S. Hatch, E. Brian Butler, Bin S. Teh. Prognostic impact of radiation therapy in mucinous carcinoma of the breast [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-19-15.

PURPOSE:The 21-gene RT-PCR recurrence score (RS) is performed in patients with hormone receptor-positive (ER+, PR+), human epidermal growth factor receptor 2 (HER2)-negative, N0 breast cancer to determine which patients will likely benefit from chemotherapy after breast-conserving surgery (BCS). The purpose of this study was to evaluate whether the RS can predict for patients likely to benefit from radiation therapy (RT) after BCS. METHODS AND MATERIALS:The National Cancer Database was queried (2004-2017) for female patients with pT1N0 ER+ PR+ HER2-negative breast cancer treated with BCS who had an available RS. Patients were stratified based on their RS (low risk [LR], 1-10; intermediate risk [IR], 11-25; high risk [HR], 26-100). For each RS cohort, propensity score matching was conducted to create 1:1 matched cohorts of patients who received RT and patients who did not. Kaplan-Meier analysis evaluated overall survival (OS). Univariable and multivariable (MVA) Cox proportional hazard analysis identified clinical and treatment factors prognostic for OS. RESULTS:A total of 79,040 patients met the selection criteria: 18,823 in the LR cohort, 52,341 in the IR cohort, and 7876 in the HR cohort. A total of 92% of patients received RT: 91% in the LR cohort, 93% in the IR cohort, and 92% in the HR cohort. After propensity score matching, the 5-year OS in the LR cohort was 95% for those who received RT and 93% for those who did not (P = .184). In the IR cohort, the 5-year OS was 95% for those who received RT and 93% for those who did not (P = .001). In the HR cohort, the 5-year OS was 95% for those who received RT and 84% for those who did not (P < .001). MVA demonstrated that RT was a positive prognostic factor for OS in both the IR cohort (P = .001) and HR cohort (P < .001). On MVA in the LR cohort, RT (P = .186) was not predictive of improved OS. CONCLUSIONS:An OS benefit was observed with the use of RT in patients with IR or HR RS but not in patients with LR RS. Future prospective evaluation is warranted.

Purpose: Tubular carcinoma (TC) is an invasive breast cancer with favorable prognosis. While pathology specific guidelines exist for TC regarding adjuvant chemotherapy and endocrine therapy, no recommendations exist regarding locoregional treatment based on tumor histology. Prognostic impact of radiotherapy for patients with TC remains unclear. Materials and methods: The National Cancer Database was queried (2004-2015) for patients with pN0M0 TC who underwent lumpectomy. Chi-square testing compared categorized variables between those who did and did not receive radiotherapy. Kaplan-Meier analysis evaluated overall survival (OS). Cox proportional hazard analysis identified variables prognostic for OS. Patients were divided into age cohorts <60 years and >60 years. Propensity score matching (PSM) was utilized to create similar cohorts. Results: 9705 patients met selection criteria; 6182 (75.1%) received radiotherapy while 2045 (24.9%) did not. After PSM, radiotherapy (HR 0.582; 95% CI 0.494-0.686) and endocrine therapy (HR 0.737; 95% CI 0.623-0.872) were favorable prognostic factors on multivariate Cox regression analysis while age > 60 years (HR 5.131; 95% CI 3.753-7.016), Black race (HR 1.445; 95% CI 1.016-2.055), and Charlson-Deyo comorbidity score > 0 (HR 1.708; 95% CI 1.403-2.079) were unfavorable prognostic factors. After PSM, 5-year OS was 91.7% for those who received radiotherapy and 84.5% for those who did not; 10-year OS was 76.1% and 64.1%, respectively (p < 0.001). Conclusion: This is the largest study to date on TC and the prognostic impact of adjuvant radiotherapy. Postoperative radiotherapy is a favorable prognostic factor for OS in patients with pN0M0 TC, suggesting adjuvant radiotherapy should remain standard of care in these patients. (c) 2021 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 159 (2021) 202-208

PurposeThe purpose of this study is to report our experience regarding the development of a staged eye-plaque brachytherapy approach for large uveal melanoma lesions which would otherwise require enucleation due to toxicity from a single-session approach.Methods and MaterialsIn an attempt to avoid enucleation from radiation toxicity, we developed a staged eye-plaque brachytherapy technique in which patients underwent 2 separate I-125 eye-plaque insertions approximately 3 months apart with a cumulative prescription dose of 90 Gy. Using this technique, we treated 2 patients who had large uveal melanomas with basal diameter plus margin at the upper limit of the largest commercially available eye-plaque.ResultsThe patients are 1- and 2-years posttreatment and both have continued tumor shrinkage with good visual acuity and very minimal appreciable radiation toxicity.ConclusionsStaged eye-plaque brachytherapy for large-diameter uveal melanoma is a novel idea used for 2 patients who would have otherwise undergone enucleation. Preliminary results suggest no local recurrence and no appreciable toxicity. Additional exploration is necessary to determine whether any subset of patients may benefit from this globe-sparing approach as standard of care.

571 Background: Based on the results of the CALGB 9343 trial, patients age ≥70 with T1N0 ER/PR+ HER2- breast cancer who are treated with breast conserving surgery (BCS) and endocrine therapy (ET) are candidates for omission of radiotherapy (RT). This trial predated the 21- gene RT-PCR recurrence score (RS) test, which is an assay now available for patients with hormone receptor positive, HER2 negative, node negative breast cancer to determine who will benefit from chemotherapy. Whether the RS can predict for patients most likely to benefit from radiation therapy (RT) following BCS has not been previously examined. The purpose of this study was to use a large database of patients age ≥70 with T1N0 ER/PR+ HER2- disease to determine if RS could predict who would benefit from RT following BCS. Methods: The National Cancer Database (NCDB) was queried (2004-2017) for female patients age ≥70 with pT1N0 ER+ PR+ HER2- breast cancer treated with BCS and ET and who had an available RS. Patients were stratified based on their RS (low risk [LR] = 1-10, intermediate risk [IR] = 11-25, high risk [HR] = 26-99). For survival analysis, propensity score matching (PSM) was conducted overall and for each group to create 1:1 matched cohorts of patients who received radiotherapy and patients who did not. Kaplan-Meier analysis with log-rank testing was used to evaluate overall survival (OS). Univariable (UVA) and multivariable (MVA) analysis were conducted using Cox proportional hazard models to determine which clinical and treatment factors were prognostic for OS. Results: A total of 13,614 patients met the selection criteria: 3,840 in the LR cohort, 8,383 in the IR cohort, and 1,391 in the HR cohort. A total of 79% received RT: 77% in the LR cohort, 79% in the IR cohort, and 85% in the HR cohort. Because PSM could not be efficiently performed in the HR cohort alone, the IR and HR cohort were merged (IRHR) for matching. After PSM, overall the 5-year OS was 90% for those who received RT and 88% for those who did not (p = 0.03). The 5-year OS in the LR cohort was 89% for those who received RT and 89% for those who did not (p = 0.517). In the IRHR cohort, the 5-year OS was 93% for those who received RT and 88% for those who did not (p = 0.004). On MVA in the overall cohort, RT (p = 0.037) was predictive of improved OS while increasing age (p < 0.001) and CDCC comorbidity score (p < 0.001) were predictive of worse OS. On MVA in the LR cohort, RT (p = 0.602) was not predictive of improved OS. However, on MVA in the IRHR cohort, RT (p = 0.004) was a positive prognostic factor for OS. Conclusions: This is the first study investigating the role of RS in this subset of patients eligible for omission of radiotherapy. There is an OS benefit with the use of RT in patients with IRHR RS, but not in patients with LR RS. Pending prospective evaluation, assessment of RS in this older subset of patients is recommended with consideration of RT when RS is ≥11.

Purpose: The utility of post-mastectomy radiotherapy (PMRT) in women with a nodal complete response (CRn) to neoadjuvant chemotherapy (NAC) is unknown. The NSABP B-51 trial is evaluating this question, but has not reported results thus far. Therefore, we sought to answer this question with the National Cancer Database. Methods: The National Cancer Database was queried for women with cT1-4N1-3M0 breast cancer who had undergone NAC and were ypN0 upon mastectomy. Statistics included multivariable logistic regres-sion, Kaplan-Meier overall survival (OS) analysis, Cox proportional hazards modeling, and construction of forest plots. Results: Of 14,690 women, 10,092 (69%) underwent adjuvant PMRT and 4598 (31%) did not. The median follow-up was 55.6 months. In all patients, the 10-year OS was 76.3% for PMRT and 78.6% without (p = 0.412). There were no notable effects of PMRT on OS based on age or the axillary management (num-ber of nodes removed). Specifically, in the NSABP B-51 population of cT1-3 cN1 patients, the 10-year OS was 82.6% for PMRT and 80.0% without (p = 0.250). PMRT benefitted women with increasing cT stage (i.e. cT3-4), increasing ypT stages (with the exception of ypT4 potentially owing to small sample sizes), and cN3 cases (p < 0.05 for all). Conclusions: In the absence of published results from NSABP B-51, this assessment of over 14,000 women from a contemporary US database revealed that PMRT may be most useful for a "moderately-high" risk group - women with more advanced primary and/or nodal disease at diagnosis, yet with tumor biology favorable enough that the disease does not progress or remain stable after NAC. The OS findings notwith-standing, this study cannot exclude potential differences between groups in recurrence-free survival, which is the primary endpoint of NSABP B-51, While the results of the NSABP B-51 will confirm optimal management for patients with limited nodal disease having a CRn following NAC, the present results sug-gest PMRT should remain the standard of care for more advanced disease than NSABP B-51 eligibility criteria. (c) 2021 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 162 (2021) 52-59

PURPOSE:Stereotactic body radiation therapy (SBRT) treatment planning for renal cell carcinoma requires accurate delineation of tumor from normal tissue due to the radiosensitivity of normal renal cortical tissue. Tc-99m dimercapto succinic acid (DMSA) renal imaging is a functional imaging technique that precisely differentiates normal renal cortical tissue from tumor. There are no prior publications reporting using this imaging modality for SBRT treatment planning.METHODS AND MATERIALS:A 59-year-old female with stage IV renal cell carcinoma progressed on systemic therapy and was dispositioned to primary cytoreduction with SBRT. She had baseline renal dysfunction and her tumor was 9 cm without clear delineation from normal tissue on conventional imaging. DMSA-single-photon emission computerized tomography (SPECT)/computed tomography (CT) was used for treatment planning.RESULTS:DMSA-SPECT/CT precisely delineated normal renal cortical tissue from tumor. Three months after treatment, labs were stable and DMSA-SPECT/CT was unchanged. The treated lesion had markedly decreased positron emission tomography avidity.CONCLUSIONS:DMSA-SPECT or SPECT/CT can be incorporated into radiation therapy planning for renal lesions to improve target delineation and better preserve renal function.

Background: Limited brain metastasis is treated definitively with stereotactic radiosurgery when surgical resection is not indicated. Although this has historically been performed in a single fraction, multi-fraction approaches such as fraction radiosurgery (FSRS) and staged radiosurgery (SSRS) have been recently examined as alternative approaches for larger lesions to permit better tumor control without increased toxicity. Case Report: We present the case of a patient who developed symptomatic radionecrosis in two brain metastasis, 2.3 cm and 2.1 cm in size, which were treated with 18 Gy in one fraction, but no radionecrosis in a 3.3 cm lesion treated in two fractions of 15 Gy nor in two punctate lesions that were treated in one fraction of 20 Gy. Although she did not respond to steroids, she responded to bevacizumab symptomatically and on neuroimaging. Conclusion: Congruent with other recent studies, our report suggests that large brain metastasis should be considered for FSRS/SSRS.

PURPOSE:Leptomeningeal disease in prostate adenocarcinoma is very rare. Solitary leptomeningeal recurrence from prostate adenocarcinoma has only been previously reported once in the published literature. METHODS AND MATERIALS:A 63-year-old man with high-risk prostate cancer was treated in a phase I-II trial with androgen deprivation, radiation therapy, and cytotoxic gene therapy. He initially had biochemical control but experienced solitary leptomeningeal recurrence 47 months after diagnosis. RESULTS:He received androgen deprivation, radiation therapy to the lumbar and sacral spine, and stereotactic radiosurgery to 3 intracranial foci of disease. He died 14 months after leptomeningeal recurrence. Autopsy showed diffuse spinal leptomeningeal disease, leptomeningeal based intracranial lesions, and no other metastasis. CONCLUSIONS:The cause for solitary leptomeningeal recurrence in this patient is unknown. Although there may be many possible mechanisms, we speculate that it could be related to his initial treatment with cytotoxic gene therapy along with radiation therapy and androgen deprivation.

Purpose: Patients with small cell lung cancer (SCLC) who have brain metastases require whole-brain radiation therapy (WBRT). When there is no emergent indication for WBRT, patients may receive systemic therapy first and WBRT afterward. In scenarios when systemic therapy is initiated first, it has not been previously investigated whether delaying WBRT is harmful. Methods and Materials: The National Cancer Database was queried (2004-2016) for patients with SCLC with brain metastases who received 30 Gy in 10 fractions of WBRT. Patients were divided into groups based on whether they received early WBRT (3-14 days after initiation of chemotherapy) or late WBRT (15-90 days after initiation of chemotherapy). Demographic and clinicopathologic categorical variables were compared between those who had early WBRT (3-14 days) and those who had late WBRT (15-90 days). Factors predictive for late WBRT were determined. Overall survival (OS), which was defined as days from diagnosis to death, was evaluated and variables prognostic for OS were determined. Results: A total of 1082 patients met selection criteria; 587 (54%) had early WBRT and 495 (46%) received late WBRT. Groups were similarly distributed aside from days from initiating chemotherapy to initiating WBRT (P < .001). The early WBRT group had a median of 7 days (interquartile range [IQR], 5-10 days) from initiating chemotherapy to initiating WBRT and the late WBRT group had a median of 34 days (IQR, 21-57 days). On binary logistic regression analysis, a longer time interval between diagnosis and the start of systemic therapy was predictive for later WBRT. Median OS was 8.7 months for early WBRT and 7.5 months for late WBRT (hazard ratio [HR], 1.165; P = .008). Early WBRT (P = .02), female sex (P = .045), and private insurance (P = .04) were favorable prognostic factors for OS on multivariable analysis, whereas older age (P = .006) was an unfavorable prognostic factor. Conclusions: Patients with SCLC and brain metastases who received early WBRT were found to have a modest improvement in OS compared with patients who received late WBRT. These findings suggest that early WBRT should be offered to patients who have brain metastases, even in the absence of an indication for emergent WBRT. (C) 2021 The Author(s). Published by Elsevier Inc. on behalf of American Society for Radiation Oncology.

BACKGROUND/AIM:Adaptive radiation therapy (ART) is a technique capable of reducing radiation dose to normal tissue without compromising local control. For potentially resectable thymoma, induction therapy is standard of care. Because large disease volume is common in this context, ART has been suggested to reduce toxicity from induction chemoradiation. This has not been previously illustrated in the literature.CASE REPORT:A 38-year-old man with initially unresectable thymoma was treated with induction chemoradiation including cisplatin and etoposide. He received 45 Gy in 25 fractions and ART was utilized to shrink the radiotherapy field for the final 10 fractions.RESULTS:Thymectomy showed Masaoka stage III disease with negative margins. He experienced no treatment-related toxicity and has no evidence of disease 8 years after diagnosis.CONCLUSION:Induction chemoradiotherapy with ART appears to be feasible, safe, and efficacious for locally advanced intact thymoma.

Background This retrospective study investigated the impact of, in addition to age, the management and outcomes of elderly patients with glioblastoma (GBM). Methods The National Cancer Database was queried between 2004 and 2015 for GBM patients age 60 years and older. Three age groups were created: 60 to 69, 70 to 79, and 80 years and older, and 4 age/KPS groups: "age ≥ 60/ KPS < 70" (group 1), "age 60 to 69/KPS ≥ 70" (group 2), "age 70 to 79/KPS ≥ 70" (group 3), and "age ≥ 80/KPS ≥ 70" (group 4). Multivariable (MVA) modeling with Cox regression determined predictors of survival (OS), and estimated average treatment effects analysis was performed. Results A total of 48 540 patients with a median age of 70 years (range, 60-90 years) at diagnosis, and a median follow-up of 6.8 months (range, 0-151 months) were included. Median survival was 5.0, 15.2, 9.6, and 6.8 months in groups 1, 2, 3, and 4, respectively (P < .001). On treatment effects analysis, all groups survived longer with combined chemotherapy (ChT) and radiation therapy (RT), except group 1, which survived longer with ChT alone (P < .001). RT alone was associated with the worst OS in all groups (P < .01). Across all groups, predictors of worse OS on MVA were older age, lower KPS, White, higher comorbidity score, worse socioeconomic status, community treatment, tumor multifocality, subtotal resection, and no adjuvant treatment (all P < .01). Conclusions In elderly patients with newly diagnosed GBM, those with good KPS fared best with combined ChT and RT across all age groups. Performance status is a key prognostic factor that should be considered for management decisions in these patients.