Survival Outcomes of Adjuvant Chemotherapy Combined With Radiation Versus Chemotherapy Alone After Pancreatectomy for Distal Pancreatic Adenocarcinoma

Objective We evaluated survival outcomes in patients with distal pancreatic ductal adenocarcinoma (D-PDAC) after distal pancreatectomy (DP) and adjuvant chemotherapy or chemoradiation. Methods A retrospective analysis of patients who underwent DP for D-PDAC from 2000 to 2015 at the Johns Hopkins Hospital was performed. Demographics, baseline risk factors, and type of adjuvant treatment were assessed for associations with overall survival (OS) and disease-free survival (DFS). Comparisons were made with log-rank tests and Cox proportional hazards regression models. Results A total of 294 patients underwent DP for D-PDAC. Of these, 105 patients were followed at the Johns Hopkins Hospital. Forty-five patients received chemotherapy only and 60 patients received chemoradiation. The median OS with chemoradiation was 33.6 months and 27.9 months (P = 0.54) with chemotherapy only. The median DFS was 15.3 months with chemoradiation and 19.8 months with chemotherapy only (P = 0.89). Elevated carbohydrate antigen 19-9, stage II to III disease, splenic vein involvement, and vascular invasion were significant risk factors in multivariate analyses. Conclusions In this retrospective analysis, there were no significant differences in OS or DFS with chemoradiation compared with chemotherapy alone after DP in patients with D-PDAC.