Adjuvant radiotherapy following pancreaticoduodenectomy for ampullary adenocarcinoma improves survival in node-positive patients: a propensity score analysis.

INTRODUCTION: This study aimed to evaluate the impact of adjuvant radiotherapy in patients undergoing pancreaticoduodenectomy (PD) for ampullary adenocarcinoma. METHODS: Using the Surveillance, Epidemiology, and End Results, patients with non-metastatic ampullary adenocarcinoma between 2004 and 2013 were identified. Cancer-specific survival and overall survival were estimated using Kaplan-Meier and Cox regression to obtain adjusted hazard ratio of survival. RESULTS: In this study, 1106 patients with ampullary adenocarcinoma were identified, of which 27% received adjuvant radiotherapy and the remaining 73% (803/1106) patients did not receive any adjuvant radiotherapy. In the matched cohort, there were still no significant difference in CSS (median 41 vs 35, p = 0.28) and OS (median 32 vs 30, p = 0.26) between patients receiving adjuvant radiotherapy and those under observation alone. However, in patients with N2 (Fig. 4) disease, both CSS (median 27 vs 19 months, p = 0.0044) and OS (median 23 vs 17 months, p = 0.0091) were significantly longer for patients receiving adjuvant radiotherapy. CONCLUSION: In summary, adjuvant radiotherapy following PD for ampullary adenocarcinoma significantly improves survival in patients with N2 disease. Future studies defining "high-risk" groups using larger cohorts will enable reliable appraisal on the benefit of adjuvant radiotherapy to allow for a more personalized approach in treating patients.