Editorial: Endoscopic Resection of Upper Gastrointestinal Subepithelial Tumors: Promising New Endoscopic Techniques-Are They Here to Stay?

Endoscopic resection of gastrointestinal subepithelial tumors originating from muscularis propria is feasible and safe if performed by experienced hands. Large tumors with predominantly extraluminal growth and extensive connection of the tumor base with the muscularis propria are associated with less complete resection and more complications. An intact tumor capsule should be used as an indication of complete resection. Free air on images after endoscopic full-thickness resection may not be an accident. Submucosal endoscopic procedures are promising therapeutic procedures but are potentially associated with serious complications. Therefore, advanced endoscopic training is needed in order to perform them correctly and safely.