Adjuvant chemotherapy versus chemoradiation in high-risk pancreatic adenocarcinoma: A propensity score-matched analysis

Abstract

Purpose: The American Society of Clinical Oncology guidelines recommend adjuvant chemoradiation (ACR) for margin-positive (R1) and/or node-positive (N+) pancreatic cancers. Our goal was to investigate if there is evidence of superiority of adjuvant chemoradiation (ACR) over adjuvant chemotherapy (AC). Methods: We utilized data from the National Cancer Database (NCDB) for N+ and/or R1 pancreatic adenocarcinoma patients diagnosed from 2004 to 2012 who underwent ACR or AC. Patients who received neoadjuvant radiation, no adjuvant treatment, or adjuvant radiation alone were excluded. Propensity score nearest-neighbor 1:1 matching (PSM) was performed between ACR and AC groups based on age, sex, race, insurance, year of diagnosis, comorbidities, tumor site and size, T-stage, nodal status, margin status, grade, and treatment facility. Primary outcome was overall survival (OS). Results: A total of 8297 patients were eligible. After PSM, two well-balanced groups of 3244 patients each were analyzed. ACR resulted in superior OS compared with AC alone (Hazard ratio [HR] 0.83, 95% CI 0.79-0.87; median OS 22 vs 19 months, P