SBRT with Sequential AG regimen +Tislelizumab+Thymalfasin
Combination ProductStereotactic body radiation therapy (SBRT): 30 ~ 40 Gy/5f, Week 1, Day 1 ~ Day 5, 6-8 Gy/time, once a day; 3 weeks as a cycle, for 4 cycles Tislelizumab: 200 mg, i.v., single infusion, 21 days as a cycle for 4 cycles, on Day 1 of each treatment cycle; Thymalfasin: 4.8 mg, subcutaneous injection, twice a week, on Day 1 and Day 4 of each week during Weeks 1 ~ 13; Albumin-bound paclitaxel: 125 mg/m2, i.v., on Day 1 and Day 8 of each treatment cycle; Gemcitabine: 1000mg/m2, i.v., on Day 1 and Day 8 of each treatment cycle; After 4 cycles of preoperative neoadjuvant therapy, radical surgery will be evaluated by the MDT team within 2-4 weeks after completion of chemotherapy + immunotherapy.