Preliminary Efficacy Analysis of "C" Single Flap Plasty Reconstruction After Laparoscopic Proximal Gastrectomy

Inclusion Criteria: 1. Age between 18-80 years old, male or female; 2. Pathological diagnosis of preoperative endoscopic biopsy: the tumor is located in the upper 1/3 of the stomach (including the esophagogastric junction), and the clinical staging of gastric cancer： Ia and Ib (T1N0M0, T1N1M0, and T2N0M0) according to the eighth edition of the AJCC ; 3. No distant metastasis was observed on preoperative chest radiograph, abdominal ultrasound, or upper abdominal CT; 4. ASA grade 1-3; 5. Patients without contraindications to surgery; 6. Patients and their families voluntarily signed the informed consent form and participated in the study; Exclusion Criteria: 1. Patients diagnosed with primary tumors or distant metastasis; 2. Patients whose tumor is located in the greater curvature side of the stomach; 3. Patients with coagulation dysfunction that could not be corrected; 4. Patients who were diagnosed with viral hepatitis and cirrhosis; 5. Patients who were diagnosed with diabetes mellitus, uncontrolled or controlled with insulin; 6. Patients with organ failure such as heart, lung, liver, brain, and kidney failure; 7. Patients with ascites or cachexia preoperatively in poor general conditions; 8. Patients diagnosed with immunodeficiency, immunosuppression, or autoimmune diseases (such as allogeneic bone marrow transplant, immunosuppressive drugs, SLE, etc.). 9. Patients refusing to sign the informed consent of the study;