Endoscopic full-thickness resection is a safe and effective method for the treatment of sigmoid schwannomas

We report the case of a 49-year-old man with a distal sigmoid schwannoma that was accidentally found during a screening colonoscopy. The patient was referred to our Center for further evaluation. Endoscopic ultrasound (EUS) confirmed the presence of a sigmoid lesion showing a well-circumscribed hyperenhancing mass of 10mm in diameter, compatible with a gastrointestinal stromal tumor. We decided to perform a full-thickness resection (FTR) of the lesion (▶Video 1). Chromoendoscopy showed the submucosal lesion located in the distal sigmoid colon, near to a previously placed endoscopic tattoo (▶Fig. 1 a). First, the edges of the lesion were marked with the FTR device (FTRD) Marking Probe (Olympus) (▶Fig. 1b), the lesion was pull into the FTRD system set (Ovesco Endoscopy) (▶Fig. 1 c) and then removed, with placement of an over-the-scope (OTS) clip (▶Fig. 1d). The resected lesion was recovered outside and placed on a cork for histological analysis (▶Fig. 2). No periprocedural complications were observed. Later the same day, after an adequate period of observation, the patient was discharged from our hospital in good general condition. At 3and 6-month follow-up, rectosigmoidoscopy showed a flat and regular scar, with nomacroscopic signs of residual tissue or recurrence, confirming the complete resection of the lesion. Schwannomas are benign, encapsulated, slow-growing, and usually solitary tumors originating from Schwann cells of the peripheral nerve sheath [1]. In the literature, only two papers have been published on the treatment of schwannomas with FTR [2, 3]. Our experience confirms that FTR, performed by experienced endoscopists, represents a safe and curative technique for the treatment of this rare neoplasm of the gastrointestinal tract. In E-Videos