LAUSR

A 72-year-old man underwent endoscopic submucosal dissection (ESD) of a 7-cm mixed-type laterally spreading tumor of the distal rectum, histologically defined as intramucosal adenocarcinoma. During subsequent surveillance, a 4-cm nonpolypoid lesion was detected on the resection scar (▶Fig. 1). We performed a novel technique for ESD, using an external additional working channel (AWC; Ovesco Endoscopy, Tübingen, Germany), called “ESD+,” to eradicate the recurrent lesion (▶Fig. 1, ▶Fig. 2, ▶Fig. 3). The procedure was conducted using a standard gastroscope. A HybridKnife I-Type (Erbe) dissector with saline solution (mixed with indigo carmine and adrenaline) as lifting fluid was used for the marking, incision, and partial dissection of the lesion. Subsequently, rescue forceps were introduced via the additional working channel to mobilize the lesion flap (▶Fig. 4) and complete the dissection (▶Fig. 5). This procedure allowed satisfactory exposure of the submucosal layer, ensuring safety and saving time in the resection of the whole lesion. The dissection was completed without complications (▶Video 1). While the use of rescue forceps via an additional working channel is widely recognized in the literature as a technique for endoscopic mucosal resection (EMR+) [1, 2], the ESD+ technique has been reported in vivo in only one recent case series, showing good results in terms of the timing and suitability of the procedure [3]. From our experience, an external working channel applied over the scope is a low-cost and safe device, and its use could improve the duration and technical feasibility of dissections of even quite large lesions without the need for a double-channel scope.