Endoscopic Resection for the Treatment of Gastric Subepithelial Tumors Originated from the Muscularis Propria Layer

Background/Aims: Endoscopic resection for pathologic diagnosis and complete eradication of subepithelial tumors (SETs) has offered less invasive alternatives to surgical resection. The aim of this study is to evaluate feasibility of endoscopic resection for the treatment of gastric SETs originated from the muscularis propria layer and to determine related factors in the success rate of endoscopic resection. Methodology: In 25 patients with a well marginated tumor which was 2 to 5cm and showed an endoluminal growth pattern according to endoscopic ultrasound (EUS) findings, endoscopic resection with incisional enucleation method was attempted in those who's SETs originated in the muscularis propria. The success rate, causes of failure, complications, EUS findings and histopathologic findings were analyzed in this retrospective single-center study. Results: Complete endoscopic resection of SETs was successful in 64% (16/25 tumors). Mean tumor size was 28.7mm (range 20-50mm). The histological diagnosis was leiomyoma for thirteen lesions and gastrointestinal stromal tumor for three lesions. The successful resection rate of tumors which had underlying muscle layer was 93.8% (15/16), but that of tumors which did not show any under EUS was 11.1% (1/9) (p<0.001). All three perforations occurred in the cases of tumors which did not show underlying muscle layer under EUS during dissection of the tumor base from surrounding tissue (p=0.037). Conclusion: Endoscopic resection for the treatment of SETs arose from the muscularis propria seems to be feasible and effective only in the well marginated tumors which showed underlying muscle layer under EUS.