Nal-IRI/5-FU/LV Chemotherapy Combined With PD-L1 Inhibitor and Multi-target Anti-angiogenic Small Molecule±SBRT as Second-line Therapy in Metastatic Pancreatic Cancer Patients

For patients with advanced metastatic pancreatic cancer who failed first-line treatment, the screening and enrollment will be completed according to the enrollment and exclusion criteria described in the study protocol, and the informed consent form will be signed after full communication. After enrollment, patients will be treated with cohort A) or cohort B), and followed up regularly. Cohort A: nal-IRI/5-FU/LV + PD-L1 inhibitor + multi-target anti-angiogenic small molecule: Irinotecan liposome: 50mg/m2 IV D1, D15 LV: 400mg/m2 IV D1, D15 5-FU ：2.4g/m2 CIV 46h D1, D15 bemosubaemab: 1200mg IV Q3W Anlotinib: 12mg po D1-D14 Q3W Cohort B: nal-IRI/5-FU/LV + PD-L1 inhibitor+ multi-target anti-angiogenic small molecule+SBRT Group: Irinotecan liposomes: 50mg/m2 IV D1, D15 LV: 400mg/m2 IV D1, D15 5-FU ：2.4g/m2 CIV 46h D1, D15 bemosubaemab: 1200mg IV Q3W Anlotinib: 12mg po D1-D14 Q3W SBRT