The Safe Study of Routine Closure of Mesenteric Defects Versus Non-closure After Radical Gastrectomy

Inclusion Criteria: * Aged 18-75 years； * Primary lesion is diagnosed with endometrial biopsy as adenocarcinoma of the stomach or esophagogastric junction, including: papillary adenocarcinoma, tubular adenocarcinoma, mucinous adenocarcinoma, poorly cohesive carcinoma (including signet ring cell carcinoma and other variants), mixed adenocarcinoma, etc.； * The gastric primary lesion is located in the antrum, body or fundus of stomach or the esophagogastric junction. It is expected that radical gastrectomy with D1+/D2 lymph node dissection achieves R0 resection (multiple primary cancers are also applicable)； * BMI(Body Mass Index) \< 30 kg/m2； * No history of upper abdominal surgery (except for laparoscopic cholecystectomy)； * No prior treatment of chemotherapy, radiotherapy, targeted therapy, immunotherapy, etc.； * Preoperative ECOG (Eastern Cooperative Oncology Group) performance status score 0 or 1； * Preoperative ASA (American Society of Anesthesiologists) scoring I-III； * Sufficient vital organ functions； * Signed informed consent. Exclusion Criteria: * Women during pregnancy or lactation； * Suffer from other malignant tumors within 5 years； * Preoperative body temperature ≥ 38°C or complicated with infectious diseases requiring systemic treatment； * Severe mental illness； * Severe respiratory disease； * Severe liver and kidney dysfunction； * History of unstable angina or myocardial infarction within 6 months； * History of cerebral infarction or cerebral hemorrhage within 6 months； * Continuous application of glucocorticoid within 1 month (except for topical application)； * Accompanied by gastric cancer complications (bleeding, perforation, obstruction, etc.) ； * The patient has participated in or is participating in other clinical studies (within 6 months).