Initially developed in Japan for the treatment of endemic superficial gastric cancers, endoscopic submucosal dissection (ESD) allows resection of pre-neoplastic and neoplastic lesions of the digestive tract into a single fragment. It allows a perfect pathological analysis, and decreases the rate of recurrence of the adenoma to less than 2%. However, this procedure, which is technically more challenging, is also more risky (perforation rate at 4% vs. 1% for WF-EMR) and longer. Submucosal dissection is also more expensive in terms of equipment, but this difference can be offset by the cost of the high number of iterative colonoscopies required in patients who have had endoscopic resection by WF-EMR. Scientific debate is agitating the Western world1,2 and Japanese experts do not perform WF-EMR anymore, whereas no comparative prospective study has compared these two procedures. A lot of centers in France performed colorectal ESD even for benign lesions and nationwide data about safety and efficiency is required to confirm the place of ESD for treatment of large superficial colorectal lesions. The aim of this French multicenter cohort is to analyze the results of colorectal submucosal dissection on a large scale.