Survival outcomes of neoadjuvant therapy followed by radical resection versus upfront surgery for stage I-III pancreatic ductal adenocarcinoma: a retrospective cohort study

Background:Neoadjuvant therapy remains controversial in treating resectable pancreatic ductal adenocarcinoma (PDAC) patients. This study aims to assess the impact of neoadjuvant therapy on survival in patients with PDAC according to their clinical stage. Methods:Patients with resected clinical Stage I-III PDAC from 2010 to 2019 were identified in the surveillance, epidemiology, and end results database. A propensity score matching method was utilized within each stage to reduce potential selection bias between patients who underwent neoadjuvant chemotherapy followed by surgery and patients who underwent upfront surgery. An overall survival (OS) analysis was performed using the Kaplan-Meier method and a multivariate Cox proportional hazards model. Results:A total of 13 674 patients were included in the study. The majority of the patients (N=10 715, 78.4%) underwent upfront surgery. Patients receiving neoadjuvant therapy followed by surgery had significantly longer OS than those with upfront surgery. Subgroup analysis revealed that the neoadjuvant chemoradiotherapy group's OS is comparable to neoadjuvant chemotherapy. In clinical Stage IA PDAC, there was no difference in survival between the neoadjuvant treatment and upfront surgery groups before or after matching. In stage IB-III patients, neoadjuvant therapy followed by surgery improved OS before and after matching compared to upfront surgery. The results revealed the same OS benefits using the multivariate Cox proportional hazards model. Conclusion:Neoadjuvant therapy followed by surgery could improve OS over upfront surgery in Stage IB-III PDAC but did not provide a significant survival advantage in Stage IA PDAC.