Endoscopic submucosal dissection and submucosal tunneling endoscopic resection of gastric subepithelial lesions originating from the muscle layer: a multicenter retrospective study.

Abstract

Background: Gastric subepithelial lesions (SELs) from the muscularis propria are usually managed surgically or with surveillance. Advances in endoscopic techniques now permit safe en bloc resection, even for lesions with extraluminal growth, but data from outside East Asia are scarce.

Methods: We performed a multicenter retrospective study across 18 centers in Europe, the Middle East, South America and South Asia, including patients with gastric SELs from the muscularis propria resected by endoscopic submucosal dissection (ESD) or submucosal tunneling endoscopic resection (STER) between 2017 and 2024. Outcomes included en bloc resection, safety, complications, and recurrence.

Results: Eighty-two patients (62.2% women; median age 59 years) were included. Median lesion size was 2cm (range 0.6-8). Lesions were located in the cardia (18.3%), fundus (18.3%), body (40.2%), and antrum (23.2%). Histology showed gastrointestinal stromal tumors in 78.0%, leiomyomas in 19.5%, and schwannomas in 2.5%. Most were endoluminal (80.5%), 19.5% were extraluminal, and 7.3% extended beyond the serosa. ESD was performed in 65.9% and STER in 34.1%. Median procedure time was 120 min. Deliberate perforation was performed in 31.7%, while 92.3% were managed endoscopically. En bloc resection was achieved in 96.3%, with defect closure in 90.2%. Complications occurred in 7%, with no mortality. Local relapse occurred in 2.5% after a median 9-month follow up. One-third of procedures took place in non-academic centers.

Conclusions: ESD and STER are safe and effective alternatives to surgery or surveillance for gastric SELs from the muscularis propria, including lesions with extraluminal growth. Long-term, comparative studies alongside laparoscopic surgery are warranted.