Evaluation of Nexpowder Application to Prevent Delayed Bleeding After Colorectal Endoscopic Mucosal Resection

Inclusion Criteria: * More than 18 years old * Indication of EMR for a superficial nonpedunculated colorectal lesion * Higher risk of bleeding (score GSEED RE2 ≥ 7\*) \*Score GSEED RE2 (Albeniz et al GIE 2020): * Proximal location (cecum to transverse included) : 3 points * Antiplatelets or anticoagulation use: 3 points * Lesion size ≥ 40 mm: 1 point * ASA III-IV or major comorbidity: 1 point Exclusion Criteria: * Patients susceptible to allergic reactions to certain substances in Nexpowder * More than one colorectal lesion * Suspicion of invasive cancer (Kudo V, Sano IIIb, Connect III), macronodular more than 1 cm, depressed area (Paris IIc) * Pedunculated polyps (Ip from Paris classification) or ulcerated polyps (III) * Recurrent or residual lesion after endoscopic or surgical resection * Poor bowel preparation quality (Boston score \< 6) * Inflammatory bowel disease (IBD) * Patients with a platelet count of 50,000/mm3 or less * Patients with acquired (non-medicated) or inherited bleeding disorders * Patients with advanced cancer or inflammatory bowel disease, including ulcerative colitis (with colonic involvement) * Contraindication to general anesthesia * Women who are pregnant or who wish to become pregnant during the study or women who are breastfeeding. * Children, immunocompromised persons and persons over 90 years of age * Patients already participating or scheduled to participate in other clinical trials * Lesion previously resected by endoscopy * Patient with an initial metastatic lesion before colonoscopy * Patient unable to give personal consent * Lack of signed informed consent