Outcomes of Neoadjuvant Chemotherapy Versus Chemoradiation in Localized Pancreatic Cancer: A Case–Control Matched Analysis

Background Neoadjuvant therapy is increasingly used for patients with pancreatic ductal adenocarcinoma (PDAC). It is unknown whether neoadjuvant chemoradiotherapy is more effective than chemotherapy (NCRT vs. NAC). We aim to compare pathological and survival outcomes of NCRT and NAC in patients with PDAC. Patients and Methods Single-center analysis of PDAC patients treated with NCRT or NAC followed by resection between December 2008 and December 2018 was performed. Average treatment effect (ATE) was estimated after case–control matching using Mahalanobis distance nearest-neighbor matching. Inverse probability weighted estimates (IPWE)-based ATE was estimated for disease-free survival (DFS) and overall survival (OS). Results Among the 418 patients (mean age 66.8 years, 51% female) included in the study, 327 received NAC and 91 received NCRT. NCRT patients had higher rates of locally advanced disease, number of neoadjuvant chemotherapy cycles, more chemotherapy regimen crossover (gemcitabine and 5-FU based), and were more likely to undergo open surgical procedures and/or vascular resection (all p