Chemotherapy Versus Chemoradiation as Preoperative Therapy for Resectable Pancreatic Ductal Adenocarcinoma: A Propensity Score Adjusted Analysis

Abstract

Objectives Although the use of neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma is increasing, the optimal preoperative treatment regimen remains poorly defined. Methods All patients with resectable pancreatic ductal adenocarcinoma who received preoperative chemotherapy alone (12%) or chemoradiation therapy (CRT) alone (88%) before pancreatectomy between 1999 and 2014 were included. Propensity score matching with inverse probability weighting was conducted based on age, baseline carbohydrate antigen 19-9, and procedure type. Results Patients who received preoperative CRT were more likely to undergo a margin negative (91% vs 79%, P < 0.01) and node negative (53% vs 23%, P < 0.01) resection and experience less locoregional recurrence (LR; 16% vs 33%, P < 0.01) but similar median overall survival (OS; 33.6 vs 26.4 months, P = 0.09). On multivariate analysis, carbohydrate antigen 19-9 (hazard ratio, 1.2; 95% confidence interval [CI], 1.1–1.3) and positive lymph nodes (hazard ratio, 1.5; 95% CI, 1.0–2.2) were associated with OS, whereas tumor size (odds ratio [OR], 1.5; 95% CI, 1.3–1.8), positive lymph nodes (OR, 3.1; 95% CI, 1.8–5.6), and preoperative chemotherapy (OR, 1.8; 95% CI, 1.1–2.9) were associated with LR. Conclusions Preoperative CRT is associated with less margin and lymph node positivity, reduced LR, and similar OS compared with preoperative chemotherapy.