A modified endoscopic full thickness resection for gastric subepithelial tumors from muscularis propria layer: Novel method.

Abstract

The removal of subepithelial tumors (SETs) is challenging, particularly in tumors originating from the muscularis propria (MP) in the upper gastrointestinal (GI) tract, owing to the high risk of perforation. We developed mechanical spray lumpectomy (MSL), which is a novel method to safely and easily remove the tumor. This study aimed to evaluate the feasibility and safety of MSL as a novel endoscopic treatment for gastric subepithelial lesions. We performed MSL in a total of 13 patients with upper GI SETs originating from the MP layer. First, mucosectomy was performed using a conventional snare. Repeated injections were performed towards the subserosal layer. After injection, the lesion was mechanically pushed to separate the MP layer using an endoscopic cap. Finally, the mucosa, submucosa, and MP layer with SETs were completely dissected using the spray coagulation mode, and the remaining defect was closed with clipping. All tumors were completely resected. The mean procedure time was 84.38±41.73min. There were four leiomyomas, six GI stromal tumors, one mucosa-associated lymphoid tissue lymphoma, and two ectopic pancreases. Although small perforation occurred in only one case, the defect was successfully closed using hemostatic clipping. Moreover, no serious complications related to MSL were encountered during or after the procedure. No residual lesion or recurrence was observed during the follow-up period. Mechanical spray lumpectomy can be a novel method that provides a safe and minimally invasive endoscopic treatment for upper GI SETs originating from the MP layer.