Safety Comparison of Total Laparoscopic Proximal Gastrectomy With or Without Preservation of the Celiac Branch of the Vagus Nerve for Early Upper Gastric Cancer: A Randomized Controlled Clinical Trial

Inclusion Criteria: 1. Age 18-75 years. 2. Histologically confirmed gastric adenocarcinoma or esophagogastric junction adenocarcinoma (papillary, tubular, mucinous, poorly cohesive including signet-ring cell carcinoma, or mixed type). 3. Primary tumor located in the upper third of the stomach, or esophagogastric junction cancer with tumor size ≤4 cm. 4. Clinical stage cT1bN0M0 without lymph node metastasis. 5. BMI \<30 kg/m². 6. No history of upper abdominal surgery (except laparoscopic cholecystectomy). 7. No prior chemotherapy, radiotherapy, targeted therapy, or immunotherapy. 8. ECOG performance status 0-1. 9. ASA class I-III. 10. Adequate organ function. 11. Signed informed consent. Exclusion Criteria: 1. Pregnancy or breastfeeding. 2. Other malignancies within 5 years. 3. Active infection requiring systemic therapy or fever ≥38°C preoperatively. 4. Severe psychiatric illness. 5. Severe respiratory disease. 6. Severe hepatic or renal dysfunction. 7. Unstable angina or myocardial infarction within 6 months. 8. Stroke or intracranial hemorrhage within 6 months. 9. Long-term systemic glucocorticoid therapy within 1 month (local use excluded). 10. Complications of gastric cancer (bleeding, perforation, obstruction). 11. Participation in another clinical study within 6 months. Exclusion During Study (Removal Criteria): R0 resection not achieved, change of procedure to total gastrectomy or PPG, combined surgery for other diseases, severe perioperative complications, emergency surgery required, patient withdrawal of consent, or protocol violation.