ObjectiveTo evaluate the clinical efficacy and safety of different stitching methods， over-the-scope-clip (OTSC) and metal clips combined with nylon rope(King closure)，for full-layer gastric wall defect. MethodsData of 75 cases, who underwent endoscopic full-thickness resection (EFTR) of gastric SMTs from May 2015 to May 2018 in our endoscopy center were retrospectively analyzed. According to the closure method, the patients were divided into the OTSC group (20 cases) and the King closure group (55 cases). Comparison was made in gender, age, the largest diameter of tumor, the location of tumor, defect surface diameter, total operating time, defect closure time, closure success rate, the length of hospital stays, cost and postoperative complications between the two groups. ResultsThe baseline data were comparable, and there were no significant differences in age, gender, tumor location, tumor diameter, and defect surface diameter between the two groups(all P＞0.05). The success rate of closure was 100% in both groups. In terms of length of hospital stay, there was no significant difference between the two groups (t=1.13, P=0.268). The total operating time was 63.24±43.22 min in the King closure group versus 47.60±18.13 min in the OTSC group (t=2.20, P=0.030).The closure time of the defect surface was 20.85±16.35 min in the King closure group versus 10.95±5.20 min in the OTSC group (t=2.65, P=0.010). Hospitalization costs were 24 200±800 yuan in the King closure group versus 36 200±2 350 yuan in the OTSC group (t=6.21, P<0.001). Postoperative abdominal elevation radiographs in both groups indicated a small amount of subphrenic free gas, and no intervention was given due to the small amount of gas and no obvious symptoms. No late bleeding, recurrent perforation, infection or other complications occurred after operation, and all patients were discharged successfully. Six months after surgery, 15 patients (27%) in the King closure group developed metal clips or nylon rope residue, which were successfully removed by endoscopy. The anastomosis clamp of nighteen patients (95%) in the OTSC group were in the original position. None of the patient received open surgery. ConclusionOTSC and King closure are both safe and effective in the treatment of full-thickness defect of gastric wall. OTSC has the advantages of short total operation time and short closure time, but with high cost.