Endoscopic enucleation for gastric subepithelial tumors originating in the muscularis propria layer.

Background: Subepithelial tumors (SETs) of the stomach are considered benign. However, they have the potential for malignant transformation, especially if they originate in the muscularis propria layer. This study aimed to determine the feasibility of endoscopic enucleation (EEN) for SETs in the muscularis propria layer and to evaluate the diagnostic efficacy and safety of EEN for SETs.

Methods: A total of 65 lesions in 64 patients were eligible for inclusion in the study during the period between June 2006 and September 2009. En bloc enucleation using an insulated-tip knife and snare was attempted for removal of gastric SETs from the muscularis propria.

Results: A total of 60 tumors were successfully resected by EEN (success rate, 92.3%). The mean tumor size, determined by endoscopic ultrasound, was 13.8 mm (range, 5-30 mm). A histologic diagnosis was obtained for 63 tumors (diagnostic yield, 96.9%), which was leiomyoma for 32 lesions, gastrointestinal stromal tumor for 26 tumors, and other for 5 tumors. The rate for complete resection in relation to the location of the lesion in the stomach was higher for the cardia, the mid/lower body (100%), and the high body (96%) than for the fundus (75%) or the antrum (50%, p=0.006). The rate of perforation was significantly higher for the fundus (50%) than for other locations (0% for the cardia and 4% for the high body) (p<0.001).

Conclusions: Endoscopic enucleation of gastric SETs originating in the muscularis propria layer was a safe and effective method for the histologic diagnosis and removal of small gastric SETs, especially those located in the cardia and the high body of the stomach.