Intraperitoneal Immune Checkpoint Inhibitors and Zoledronic Acids for Gastric Cancer Malignant Ascites

Inclusion Criteria: * Gastric adenocarcinoma diagnosed pathologically; * Malignant ascites confirmed by ascites cytology; * Presence of ascites confirmed by CT with ascites graded as 2nd and 3rd degree (EASL guidelines and ICA consensus); * Those aged 18-75 years; * Patients who had not undergone local administration of drugs in the abdominal cavity and systemic immunotherapy within the previous 4 weeks; * Vital signs are stable, Karnofsky score (≥70), and expected survival time is \>3 months; * Normal bone marrow haematopoietic function, blood routine: HGB ≥90g/L, WBC ≥2.5×10\^9/L (NEU ≥1.5×10\^9/L), PLT ≥90×10\^9/L; * Normal coagulation function without bleeding tendency (International normalised ratio of prothrombinogen INR\<1.5); * Liver function: total bilirubin ≤1.5 times the upper limit of normal (ULN); AST and ALT ≤2 times the upper limit of normal (ULN) (or ≤5 times the upper limit of normal (ULN) if the abnormalities are mainly due to tumour infiltration); * Renal function: Cr ≤1.5 times the upper limit of normal (ULN) or creatinine clearance ≥60mL/min. Exclusion Criteria: * Non-malignant ascites (e.g., portal hypertension ascites or infected ascites); * Presence of contraindications to immunotherapy (including long-term hormone use, history of radiation pneumonitis, radiation hepatitis, radiation enteritis, etc.); * Combination of other serious cardiopulmonary diseases that affect the treatment, etc; * Patients with extensive abdominal adhesions; encapsulated pe…