Inclusion Criteria:  Patients aged 18 years or older that fulfil only WHO criteria 2 of SPS and did not fulfil WHO criteria 1.  Criteria 1: any patient with ≥ 5 SL proximal to the rectum, all ≥5 mm in size, with at least 2 ≥10 mm in size. Criteria 2: any patient with >20 SL of any size distributed throughout the colon, with ≥5 lesions proximal to the rectum. Patients with a previous complete colonoscopy with adequate bowel preparation and with all lesions >5mm been resected ("clearance colonoscopy), after the diagnostic of SPS. Nor advanced adenoma or serrated lesions at prior colonoscopy, and also either more than 5 relevant lesion (adenoma, SSL or PH>5mm) at prior colonoscopy.  Exclusion Criteria:  Patients with no inform consent or who do not agree to participate in the study. Patients with total or partial colectomy. Patients with other CCR predisposing syndromes with germinal mutation (Familial adenomatous polyposis, Lynch syndrome, Peutz-Jehgers syndrome, Cowden syndrome, Juvenile polyposis syndrome…). Patients with chronic inflammatory bowel disease. Patients with coagulation disorders. Fragmented lesion or submucosal invasive lesion at last colonoscopy. Inadequate colon preparation: any segment of the colon with <2 points in Boston Scale (BBPS).