Adjuvant radiation provides survival benefit for resected pancreatic adenocarcinomas of the tail.

Background: The appropriate adjuvant treatment for resected pancreatic cancer remains a controversy. We sought to determine the effect of adjuvant treatment on overall survival (OS) in patients with pancreatic tail adenocarcinoma.

Methods: Retrospective review of patients with upfront surgically resected pancreatic tail cancer treated at our institution between 2000-2012 was performed to determine outcomes of patients treated with and without adjuvant radiation therapy (RT). Survival curves were calculated according to the Kaplan-Meier method. Univariate analysis (UVA) and multivariate analysis (MVA) were performed using the Cox proportional hazards model.

Results: Thirty-four patients met inclusion criteria. 79% received adjuvant chemotherapy, either concurrent with RT or alone. The groups were well matched, with the only significant difference being patient sex. On both UVA and MVA there was significantly worse survival in patients with a post-op CA19-9 >90 [hazard ratio (HR) 5.55; 95% confidence interval (CI): 1.20-25.7, P=0.03] and improved survival in patients treated with adjuvant RT (HR 0.15; 95% CI: 0.04-0.58, P=0.006). The median and 2-year OS were 21.6 months and 47% for patients treated with adjuvant RT compared with 11.3 months and 21% for those treated without RT.

Conclusions: Although few in patient numbers, this data suggests integration of adjuvant RT in resected pancreatic tail adenocarcinoma may improve OS.