A Study of GnP RegimenCombined With Serplulimab and Stereotactic Body Radiation Therapy as First-line Treatment for Locally Advanced Pancreatic Cancer

This study is a single-arm phase II clinical trial. The study targets patients aged 18-75 years with ECOG performance status 0-2, diagnosed with locally advanced pancreatic ductal adenocarcinoma based on comprehensive assessment of pathology and imaging studies (CT or MRI). Participating patients will receive the GnP regimen every 21 days (nab-paclitaxel 125mg/m² ivgtt on days 1 and 8 + gemcitabine 1000mg/m² ivgtt on days 1 and 8, repeated every 21 days) combined with serplulimab (200mg ivgtt Q3W). In the second cycle, patients will receive SBRT targeting the primary tumor and/or retroperitoneal lymph nodes: 6.6Gy×5 fractions, 7Gy×5 fractions, or 8Gy×5 fractions, administered every other day with radiotherapy completed in 5 sessions (specific selection determined by investigators based on lesion size and organs at risk \[OAR\] assessment). Comprehensive evaluation including tumor markers and CT scans will be performed every 2 cycles with multidisciplinary team (MDT) review, and patients who meet surgical criteria will undergo radical resection surgery.