Efficacy and safety of stereotactic body radiation therapy combined with immune checkpoint inhibitors in locally advanced pancreatic cancer: A retrospective analysis

Locally advanced pancreatic cancer (LAPC) remains a major therapeutic challenge with poor prognosis. This study aimed to evaluate the efficacy and safety of stereotactic body radiation therapy (SBRT) combined with immune checkpoint inhibitors (ICIs) in patients with LAPC. In this retrospective cohort study, 107 patients with histologically confirmed LAPC treated between January 2020 and December 2022 were analyzed. Patients were divided into two groups based on the treatment they received: SBRT + ICIs (n = 46) and SBRT alone (n = 61). The primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary outcomes included objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events. Prognostic factors for OS and PFS were assessed by Cox regression analyses. The SBRT + ICIs group showed significantly improved median OS ( P = 0.012) and median PFS ( P = 0.031) compared to the SBRT group. ORR was significantly higher in the combination group ( P = 0.008), as was DCR ( P = 0.020). Immune-related diarrhea and skin rash were more frequent in the combination group ( P < 0.05), while the overall incidence of Grade ≥3 adverse events was comparable between groups ( P = 0.219). Multivariate analysis identified combination therapy, younger age, smaller tumors, and lower CA19-9 independently predicted longer OS and PFS (P < 0.05). SBRT plus ICIs improved survival and response in LAPC, was independently linked to better prognosis, and was well tolerated, supporting its potential as an effective therapeutic strategy for LAPC.