A Tale of Two Cities: Reconsidering Adjuvant Radiation in Pancreatic Cancer Care

Adjuvant chemotherapy plays a critical role in the treatment of resected pancreatic cancer patients. However, the role of adjuvant radiation remains controversial. This study compares survival between resected pancreatic cancer patients who received adjuvant radiation and no adjuvant radiation. Medical records of patients with pancreatic ductal adenocarcinoma who underwent surgical resection from January 2003 through 2013 at medical centers in Boston and Leiden were retrospectively reviewed. Propensity score matching was used to correct for potential selection bias in the allocation of adjuvant chemoradiation versus chemotherapy alone. Three hundred fifty total patients were identified, of whom 138 (39.4 %) received adjuvant radiation. On pathological staging, 245 (70.0 %) had positive lymph nodes, and these patients gained a significant survival benefit from adjuvant radiation (hazard ratio (HR) 0.74; 95 % confidence interval (CI) 0.56-0.99) in the complete cohort. After propensity score matching, adjuvant radiation lost its prognostic significance in the complete cohort. However, after matching, patients who survived longer than 12 months and had positive lymph nodes (n = 108) demonstrated a significant (log-rank p = 0.04) survival benefit from adjuvant radiation. This study, while non-randomized, suggests that adjuvant radiation may be associated with a survival benefit for resected pancreatic cancer patients in specific situations.