Tislelizumab Combined With Nab-paclitaxel and Gemcitabine for Recurrent Pancreatic Cancer

Inclusion Criteria: * Patients with radiologically or histologically confirmed postoperative Recurrent Pancreatic Cancer * Patients with at least one measurable lesion (according to RECIST 1.1 criteria); * Have not received gemcitabine-based regimen after surgery * No systemic treatment after diagnosis of recurrence * ECOG score 0-1 * Expected survival ≥ 3 months; * Liver function is essentially normal: absolute neutrophil count \> 1500/mm ³; platelet count \> 100,000/mm ³; creatinine less than 1.5 times the upper limit of normal or calculated creatinine clearance (CRCI) \> 45 mL/min; total bilirubin ≤ 2.0 mg/dL; aspartate aminotransferase (AST) and alanine aminotransferase less than 2.5 times the upper limit of normal * Appropriate to participate in this trial as assessed by the investigator before entering the study * Male and female subjects of childbearing potential must agree to use an effective method of contraception throughout the study * Signed Informed Consent Form Exclusion Criteria: * Patients who only undergo abdominal laparotomy but do not undergo resection of pancreatic tumor tissue * Received gemcitabine-based regimen after surgery * Systemic treatment after diagnosis of recurrence * Patients with previous allergic reactions to similar drugs * Pregnant or lactating patients * Presence of pericardial effusion, uncontrolled pleural effusion, or clinically significant ascites at screening (including detectable ascites or ascites requiring puncture and aspiration on physical examination at screening) * History of interstitial lung disease, pneumonitis, or uncontrolled systemic disease, including diabetes, hypertension, pulmonary fibrosis, acute lung disease, etc * Patients with severe cardiovascular diseases within 12 months before enrollment, such as symptomatic coronary heart disease, ≥ grade II congestive heart failure, uncontrolled arrhythmia, myocardial infarction, etc * Presence of any active immunodeficiency or autoimmune disease and/or history of any immunodeficiency or autoimmune disease that may recur at screening (e.g., hypothyroidism or hyperthyroidism, interstitial pneumonia, enteritis, hepatitis, hypophysitis, vasculitis, myocarditis, etc) * Use of steroids or other systemic immunosuppressive therapy 14 days prior to enrollment * Patients with other previous malignancies who are not cured * Immunodeficient patients, such as HIV-positive * Uncontrollable psychosis