The AWC was used in 8 patients with GI lesions 17-45 mm (average 35.9 mm) in size for EMR with modified grasp-and-snare technique (4 cases) or ESD (4 cases). R0-resection was achieved in 6 cases. Complications were acute arterial bleeding post-EMR in two cases treated by endoscopic clipping.
Walter B et al., Department of Gastroenterology, InExEn, University Hospital Ulm, Ulm, Germany reported on the use of the AWC (Additional Working Channel) in eight patients with large, flat lesions or early stages of cancer in the upper or lower gastrointestinal tract.
Endoscopic en-bloc resection of large, flat GI lesions is challenging. No bimanual tasks are possible using standard endoscopes. Dual-channel endoscopes are not available everywhere and have a small distance between the channels. The AWC can be fixed to the tip of a standard gastroscope or pediatric colonoscope, a second endoscopic tool can be inserted through the AWC and used for a distinct tissue traction and counter-traction during endoscopic resection, as the distance between working channels can be adjusted.
Eight patients with large, flat lesions or early stages of cancer in the upper or lower gastrointestinal tract were treated with endoscopic mucosal resection (EMR) with a modified grasp-and-snare technique (4 cases) and endoscopic submucosal dissection (ESD, 4 cases) using the AWC. Mean procedure time (scope-in to scope-out) was 68.5 minutes. R0-resection was achieved in all of the four cases treated by ESD and in two cases treated by EMR. The remaining two cases were treated by piecemeal EMR with positive lateral margins. Complications were acute arterial bleeding post-EMR in two cases treated by endoscopic clipping. No delayed bleeding, no perforation and no further severe adverse events occurred.
The authors concluded that the AWC enables endoscopic resection of large lesions in the upper and lower gastrointestinal tract. Benefits are its suitability for EMR and ESD, no need for a dual-channel endoscope and an adjustable distance of working channels.
Improved endoscopic resection of large flat lesions and early cancers using an external additional working channel (AWC): a case series.
Walter B, Schmidbaur S, Krieger Y, Meining A.
Endoscopy International Open 2019;07: E298-E301.