BACKGROUND: Needle knives are the most commonly used instrument during endoscopic treatment for gastric submucosal tumors (SMTs). The conventional resection method involves fully extending the needle-shaped knife head, which allows it to more easily penetrate the muscularis propria while stripping the muscle layer of the tumor. We propose a semi-blunt dissection method that can effectively reduce damage to the muscularis propria. METHODS: A total of 113 patients who underwent endoscopic resection of gastric SMTs originating from the muscularis propria were retrospectively analyzed. The conventional method consisted of 73 patients
The other group consisted of 40 patients underwent the semi-blunt dissection method. RESULTS: There was no significant difference between the two groups in age, sex, or lesion location. The intraoperative operational variable, the maximum diameter of gastric muscularis propria damage, was significantly greater in conventional method group than the other group (1.06 ± 0.48 cm vs. 0.46 ± 0.09 cm, p <
0.001). There was also no significant difference between the two groups in terms of histological diagnosis, postoperative complications and the percentage of histologically positive resection margins. CONCLUSION: The semi-blunt dissection method has certain advantages in the endoscopic resection of gastric tumors originating from the muscularis propria, including a small extent of gastric muscularis propria damage and a shorter postoperative hospital stay.