The Impact of Adjuvant Radiotherapy on Survival in Patients with Surgically Resected Pancreatic Adenocarcinoma - A SEER Study from 2004 To 2010

Objectives The utility of adjuvant external beam radiation therapy after surgery for pancreatic adenocarcinoma remains controversial. Our aim was to identify subsets of patients who may benefit from adjuvant external beam radiation therapy. Methods 6114 patients with pancreatic adenocarcinoma treated with oncologic surgery between 2004 and 2010 were extracted from the SEER database. Demographic and treatment information was obtained for these patients, including whether or not patients received adjuvant external beam radiation therapy. A Cox multivariable analysis was performed to provide an adjusted hazard ratio of dying from pancreatic cancer. Results The adjusted hazard ratio of dying from pancreatic cancer favored the adjuvant external beam radiation therapy arm (HRDPC=0.75, 95% CI 0.70-0.79, p<0.0001). Unfortunately, it was not possible to elucidate subsets of patients who may or may not share the benefit of adjuvant external beam radiation therapy based on prognostic factors or treatment approaches. Interestingly, the hazard ratio of dying from pancreatic cancer for the overall population was statistically significantly improved in 2009 and 2010 as compared to 2004. The hazard ratio of dying from pancreatic cancer did not significantly improve in the adjuvant external beam radiation therapy population with time. Discussion For the overall population in the SEER database, patients receiving adjuvant EBRT after surgery are at decreased risk of dying from pancreatic cancer. Received January 28th, 2016 Accepted February 28th, 2016