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Purpose: Gastrointestinal injury occurs rarely with agents that affect the vascular endothelial growth factor receptor and with abdominal stereotactic body radiation therapy (SBRT). We explored the incidence of serious bowel injury (SBI) in patients treated with SBRT with or without vascular endothelial growth factor inhibitor (VEGFI) therapy., Methods and Materials: Seventy-six patients with 84 primary or metastatic intra-abdominal lesions underwent SBRT (median dose, 50 Gy in 5 fractions). Of the patients, 20 (26%) received VEGFI within 2 years after SBRT (bevacizumab, n=14; sorafenib, n=4; pazopanib, n=1; sunitinib, n=1). The incidence of SBI (Common Terminology Criteria for Adverse Events, version 4.0, grade 3-5 ulceration or perforation) after SBRT was obtained, and the relationship between SBI and VEGFI was examined., Results: In the combined population, 7 patients (9%) had SBI at a median of 4.6 months (range, 3-17 months) from SBRT. All 7 had received VEGFI before SBI and within 13 months of completing SBRT, and 5 received VEGFI within 3 months of SBRT. The 6-month estimate of SBI in the 26 patients receiving VEGFI within 3 months of SBRT was 38%. No SBIs were noted in the 63 patients not receiving VEGFI. The log-rank test showed a significant correlation between SBI and VEGFI within 3 months of SBRT (P=.0006) but not between SBI and radiation therapy bowel dose (P=.20)., Conclusions: The combination of SBRT and VEGFI results in a higher risk of SBI than would be expected with either treatment independently. Local therapies other than SBRT may be considered if a patient is likely to receive a VEGFI in the near future., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: The management of patients diagnosed with thymoma remains unclear. This report attempts to identify the impact of adjuvant radiotherapy on overall survival (OS) and cause-specific survival (CSS) in patients diagnosed with thymoma., Methods and Materials: Patients diagnosed with thymic malignancy between 1973 and 2003 were retrospectively identified from centers participating in the Surveillance, Epidemiology, and End Results (SEER) program. Those patients classified as having thymic carcinoma were excluded from this analysis. OS and CSS were estimated by the Kaplan-Meier method. Outcomes for patients treated with and without radiation therapy were compared using the log-rank test. Multivariate analysis was performed with the Cox proportional hazards model to analyze factors predictive of OS and CSS., Results: A total of 1,464 patients were identified as having thymic malignancy, and of these, 1,254 patients were identified as having malignant thymoma. The median follow-up time was 41 months (range, 4-337 months). Among patients who did not receive radiotherapy (RT), the 10-year rate of OS was 41% compared to 42% for those who did receive RT (p = 0.06). The median OS for the patients who did not receive RT was 80 months compared to 97 months for those who did receive RT. In patients with Masaoka stage II-III malignancy, OS was significantly improved with RT (p = 0.002), and a trend in improved CSS was observed (p = 0.1). Patients were also analyzed based on resection status. For those patients who had an incomplete excision, the 10-year OS was 63% with RT and 46% without RT (p = 0.38). On multivariate analysis, factors predictive of OS included age, extent of surgery, stage, and number of lymph nodes examined., Conclusions: This study reports treatment results of a large cohort of patients who were diagnosed with malignant thymoma. This study demonstrates that the use of RT following resection for thymoma significantly improves OS for those with regional disease and marginally improves CSS., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: The benefit of adjuvant radiotherapy (RT) after surgical resection for extrahepatic cholangiocarcinoma has not been clearly established. We analyzed survival outcomes of patients with resected extrahepatic cholangiocarcinoma and examined the effect of adjuvant RT., Methods and Materials: Data were obtained from the Surveillance, Epidemiology, and End Results (SEER) program between 1973 and 2003. The primary endpoint was the overall survival time. Cox regression analysis was used to perform univariate and multivariate analyses of the following clinical variables: age, year of diagnosis, histologic grade, localized (Stage T1-T2) vs. regional (Stage T3 or greater and/or node positive) stage, gender, race, and the use of adjuvant RT after surgical resection., Results: The records for 2,332 patients were obtained. Patients with previous malignancy, distant disease, incomplete or conflicting records, atypical histologic features, and those treated with preoperative/intraoperative RT were excluded. Of the remaining 1,491 patients eligible for analysis, 473 (32%) had undergone adjuvant RT. After a median follow-up of 27 months (among surviving patients), the median overall survival time for the entire cohort was 20 months. Patients with localized and regional disease had a median survival time of 33 and 18 months, respectively (p<.001). The addition of adjuvant RT was not associated with an improvement in overall or cause-specific survival for patients with local or regional disease., Conclusion: Patients with localized disease had significantly better overall survival than those with regional disease. Adjuvant RT was not associated with an improvement in long-term overall survival in patients with resected extrahepatic bile duct cancer. Key data, including margin status and the use of combined chemotherapy, was not available through the SEER database., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Purpose: Proton radiotherapy (PT) and stereotactic body radiotherapy (SBRT) have the capacity to optimize the therapeutic ratio. We analyzed the dosimetric differences between PT and SBRT in treating primary peripheral early-stage non-small-cell lung cancer., Methods and Materials: Eight patients were simulated, planned, and treated with SBRT according to accepted techniques. SBRT treatments were retrospectively planned using heterogeneity corrections. PT treatment plans were generated using single-, two-, and three-field passively scattered and actively scanned proton beams. Calculated dose characteristics were compared., Results: Comparable planning target volume (PTV) median minimum and maximum doses were observed between PT and SBRT plans. Higher median maximum doses 2 cm from the PTV were observed for PT, but higher median PTV doses were observed for SBRT. The total lung mean and V5 doses were significantly lower with actively scanned PT. The lung V13 and V20 were comparable. The dose to normal tissues was lower with PT except to skin and ribs. Although the maximum doses to skin and ribs were similar or higher with PT, the median doses to these structures were higher with SBRT. Passively scattered plans, compared with actively scanned plans, typically demonstrated higher doses to the PTV, lung, and organs at risk., Conclusions: Single-, two-, or three-field passively or actively scanned proton therapy delivered comparable PTV dose with generally less dose to normal tissues in these hypothetic treatments. Actively scanned beam plans typically had more favorable dose characteristics to the target, lung, and other soft tissues compared with the passively scanned plans. The clinical significance of these findings remains to be determined.

Purpose: A retrospective study to evaluate the outcome of salvage radiotherapy (RT) for clinically apparent, palpable prostate cancer recurrence after radical prostatectomy (RP)., Methods and Materials: Forty-two patients underwent RT for clinically apparent recurrent prostate cancer after RP between 1993 and 1999. The end points and treatment variables of biochemical disease-free survival were evaluated statistically., Results: The median follow-up was 4.3 years. All 42 patients experienced resolution of clinically detectable recurrence within 1 year after RT. The 5-year biochemical disease-free survival, local control, freedom from distant metastases, and overall survival rate was 27%, 94%, 82%, and 78%, respectively. The initial pathologic stage (T3 or T4; p = 0.04) and interval (<2 years from RP to RT; p = 0.01) were independent predictors of biochemical failure, and RT simulation without contrast (p = 0.05) was nearly significant on multivariate analysis. Three patients (7%) experienced chronic Grade 3 or 4 RT-related toxicity., Conclusion: Salvage prostate bed RT for clinically apparent locally recurrent prostate cancer after RP provides effective local tumor control with modest durable biochemical control. Patients irradiated with a better simulation technique were found to have a more favorable outcome. A consensus on a definition of biochemical disease-free survival after salvage RT is critical for meaningful comparison of the available data and to future progress in treating this disease process.