Endoscopic submucosal dissection and submucosal tunneling endoscopic resection of gastric subepithelial tumors originating from the muscle layer. A multicenter retrospective study

Aims Gastric subepithelial lesions (SELs) arising from the muscularis propria have traditionally been managed surgically or with routine follow-up due to the low metastasis risk. Until recently, endoscopic resection was avoided due to perforation risks. Advances in endoscopic technology and closure techniques now enable safe en-bloc resections, though adoption remains limited, and data on submucosal tunneling endoscopic resection (STER) and endoscopic submucosal dissection (ESD) for these lesions are scarce. This study evaluates the feasibility, safety, and short-term clinical outcomes of these techniques in international centers.

Methods We conducted a multicenter retrospective analysis across 18 centers in Europe, the Middle East, and South Asia, examining cases of gastric SELs arising from the muscularis propria and resected via ESD or STER between 2017 and 2024. Outcomes included en-bloc resection rate, procedural safety, complication rates, and follow-up recurrence.

Results The study included 82 patients (62.2% female; median age 59 years, range 20–81). Median lesion size was 2 cm (0.6–8 cm), located in the cardia, fundus, body, and antrum in 18.3%, 18.3%, 40.2%, and 23.2% of cases, respectively. Gastrointestinal stromal tumors constituted 78.0% of cases, with leiomyomas and schwannomas comprising 19.5% and 2.5%, respectively. Most tumors (80.5%) were endoluminal; 19.5% exhibited extraluminal growth, and 7.3% extended beyond the serosa. ESD was performed in 65.9% of cases, and STER in 34.1%, with a median procedure time of 120 minutes (24–305), comparable across techniques. Deliberate perforation occurred in 31.7% of cases, managed endoscopically with mucosal flaps or suturing. En-bloc resection was achieved in 96.3%, and endoscopic defect closure was successful in 90.2% of cases (51.4% with through-the-scope clips, 35.1% with loop-and-clip, 9.5% with suturing, and 4.1% with over-the-scope clips). Complications occurred in 7% of cases (perforation, bleeding, conversion to surgery, peritonitis, or prolonged hospitalization). Local relapse was observed in 2.5% of cases after a median follow-up of 9 months (range 3–60 months).

Conclusions Endoscopic resection of gastric SELs originating from the muscularis propria using ESD or STER is a feasible, safe, and effective alternative to surgery or surveillance in specialized centers. Technological advancements in defect closure facilitate deeper resections, including beyond the serosa. While promising, long-term and comparative studies are warranted to further validate these methods as alternatives to laparoscopic surgery or routine follow-up.

Publication History

Article published online:
27 March 2025