Adebrelimab Plus S-1 for Resected Cholangiocarcinoma

Inclusion Criteria: * Histologically or pathologically confirmed malignant cholangiocarcinoma. * Patients who have undergone curative surgical resection. * Age between 18 and 75 years. * Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. * Expected survival time \>3 months. * Adequate organ and bone marrow function, including:Absolute neutrophil count ≥1.5 × 10\^9/L,Platelet count ≥75 × 10\^9/L,Hemoglobin ≥90 g/L,Total bilirubin ≤1.5 × upper limit of normal (ULN),AST and ALT ≤2.5 × ULN,Albumin ≥3 g/dL,Serum creatinine ≤1.5 × ULN. * Ability to understand and willingness to sign written informed consent. * For patients of childbearing potential, willingness to use effective contraception during the study and for at least 1 month after the last dose; negative pregnancy test within 72 hours prior to enrollment. Exclusion Criteria: * Prior treatment with immune checkpoint inhibitors or other agents targeting T-cell co-stimulatory or co-inhibitory pathways (e.g., CTLA-4, CD137). * Use of any investigational drug within 4 weeks prior to enrollment. * Active autoimmune disease or history of autoimmune disease (e.g., interstitial lung disease, uveitis, enteritis, hepatitis, hypophysitis, vasculitis, myocarditis, nephritis, hyperthyroidism, or hypothyroidism requiring hormone replacement). * Known immunodeficiency, including HIV infection, active hepatitis B (HBV DNA \>500 IU/mL), active hepatitis C (HCV RNA above detection limit), or co-infection of HBV and HCV…