Abstract Background To evaluate the impact of radiation dose on overall survival (OS) in patients treated with adjuvant chemoradiation (CRT) for pancreatic ductal adenocarcinoma (PDAC). Methods A multicenter retrospective analysis on 514 patients with PDAC (T1–4; N0–1; M0) treated with surgical resection with macroscopically negative margins (R0–1) followed by adjuvant CRT was performed. Patients were stratified into 4 groups based on radiotherapy doses (group 1: