Removal of a large, 40-mm, submucosal leiomyoma using submucosal tunneling endoscopic resection and extraction of specimen using a distal mucosal incision.

Submucosal tunneling endoscopic resection (STER) combines the techniques of peroral endoscopic myotomy [1] and endoscopic submucosal dissection for removal of upper gastrointestinal tract submucosal tumors (SMTs). STER has beenused for removal of small SMTsbelow 20mmwith low complication rates [2–4]. This report describes the removal of a large 40-mm esophageal SMT using STER, and describes a novel technique to aid the en bloc extraction of large SMTs during STER. A 57-year-old man presented with dysphagia. Upper endoscopy (●" Video1) and endoscopic ultrasound (●" Fig.1) confirmed a 40-mm SMT in the mid esophagus. The novel technique used for the removal of the SMT is shown in●" Fig.2. A single-channel endoscope with a transparent distal cap attachment was used. Following injection of diluted indigo carmine, a mucosal incision was made using a triangle tip knife, 4cm proximal to the tumor. A submucosal tunnel was created towards the tumor (●" Video2), and peritumoral dissection was accomplished by division of submucosal fibers and attachments (●" Video3). After completion of peri-tumoral dissection, removal of the SMT by various endoscopic retrieval devices, including snares andnets,was unsuccessful because of the size of the SMT and the limited working space available within the submucosal tunnel (●" Video4). A novel second distal mucosal incision technique was performed for en bloc removal of the resected specimen, as illustrated in ●" Fig.3. A submucosal tunnel was created 4cm distal to the tumor, and a mucosal incision was made from within the submucosal tunnel (●" Video4). The SMTwas thenpushedusing the endoscope from the submucosal tunnel into the true lumen of the distal esophagus and into the stomach through thedistalmucosal incision.With adequateworking space in the stomach, a net could be deployed easily over the SMT, and the SMTwas retrieved.