LAUSR

Endoscopic submucosal dissection (ESD) has been the preferred treatment of small gastrointestinal neuroendocrine tumors (NETs) (≤10mm) without muscularis propria invasion [1]; however, the requirements of special instruments and complex skills have limited its widespread application [2]. In this regard, we developed a simple clip-and-snare assisted endoscopic mucosal resection (CS-EMR) technique for complete removal of a rectal NET (▶Video 1). A 35-year-old man was referred for endoscopic treatment of a small rectal NET (6mm). Because the NET was seen on colonoscopy to have a flat subepithelial surface (▶Fig. 1 a) and was evaluated on endoscopic ultrasonography (EUS) as not showing invasion of the muscularis propria, CS-EMR was used to achieve complete resection. As the transparent capcovered single-channel endoscope, along with a pre-anchored snare, entered the rectum to target the tumor, a clip was inserted through the working channel of the endoscope and was used to grasp the mucosa adjacent to the tumor (▶Fig. 1b). When the NET had been well lifted by the clip and transformed into a “pedicle polyp,” the snare was released from the endoscope and completely enveloped the root of the NET (▶Fig. 1 c). The NETwas fully excised using a blended electrosurgical current (▶Fig. 1d), leaving a clean surgical wound (▶Fig. 1 e). The wound was immediately closed by the lifting clip and application of a further clip (▶Fig. 1 f). Histological examination of the resected specimen revealed a G1 NETwith negative margins (▶Fig. 2). Unlike the previously reported graspand-snare EMR, which requires a dualchannel endoscope to deploy a snare and a biopsy forceps through each channel [3], this CS-EMR needs only a single-channel endoscope. Unlike with the “underwater” EMR technique, which may be affected by blind vision once bleeding occurs [4], the CS-EMR has no risk of causing bleeding before resection. Therefore, the easy and safe CS-EMR technique is a promising alternative to replace ESD in the treatment of small NETs.