Inclusion Criteria:  pathological diagnosis of gastric cancer clinically diagnosed cT1b-3N0-2M0 lesions according to the 8th Edition of the American Joint Committee on Cancer(AJCC) Cancer Staging Manual(measured using abdominal CT) tumor size ≤ 5cm planned to conduct subtotal gastrectomy  Exclusion Criteria:  preoperative radiotherapy and chemotherapy tumor perforation severe mental disease