The anal canal epithelium. A review.

AbstractObjective: The use of mucosal traction to assist in colonic and rectal endoscopic submucosal dissection (ESD), especially for deep colonic ESD, is challenging. We developed a method of inverse insertion of a snare into the endoscopic working channel to deliver it into the colon together with the endoscope. With this method, two types of mucosal traction, per-anal external traction (PET) and per-anal internal traction (PIT), could be achieved using a snare with endoclips to assist in ESD (ESD-SE). Here, we aimed to examine its safety and feasibility.Methods: From January 2017 to September 2018, 50 colonic and rectal intraepithelial neoplasias in 50 patients were treated with ESD-SE. Data on lesion location and size, operation time, en bloc resection and R0 resection rates, and operative complications were collected.Results: Among 50 lesions, 15 lesions were located in the deep colon/proximal colon, and 35 lesions were in the distal colon. The median (interquartile range) size of lesions, submucosal...