Exploring prognostic factors for survival in patients with advanced pancreatic cancer undergoing PD-1 inhibitor immunotherapy

Immunotherapy, led by programmed cell death protein-1 (PD-1) inhibitors, has emerged as a prominent antitumor therapy, yet prognostic challenges persist in pancreatic cancer (PC). This retrospective, single-center study evaluated prognostic factors in advanced PC patients treated with PD-1 inhibitors at the PLA General Hospital's Oncology Department from 2015–2022. With ethics approval by the Ethics Committee of the General Hospital of the People's Liberation Army (S2021-228-03), we analyzed 126 patients using Kaplan-Meier and Cox models. p < .05 was considered a statistically significant difference. Median overall survival (mOS) and progression-free survival (mPFS) were 12.1 and 4.6 months, respectively. Significant mOS predictors were surgery history (44.2 months vs. 10 months, *p = .022), absence of liver metastases (44.2 months vs. 6.4 months, *p = .034), and baseline CA19–9 ≤ 216.15 U/ml (18.5 months vs. 9.2 months, *p = .049). For mPFS, histologic differentiation (5.5 months vs. 3.2 months, *p = .022) and first-line PD-1 inhibitor use (5.1 months vs. 1.5 months, ***p = .001) were key. Subgroup analyses highlighted early progression in low histologic differentiation and earlier death without surgery. History of surgery, absence of liver metastases, baseline CA19–9 level, and histologic intermediate/high differentiation may predict PD-1 inhibitor efficacy in advanced PC, pending validation in prospective trials.