Safety of a long-term endoscopic surveillance protocol for serrated polyposis patients

Interventions: Data are collected in prospective manner from patients during routine surveillance endoscopies with removal of all polyps > 3 mm and/or with a adenomatous aspect. Primary outcome(s): - Incidence of interval colorectal cancer during protocolled endoscopic surveillance of SPS patients Study Design: N/A: single arm study, Open (masking not used), N/A , unknown, Other