Long-term follow-up after removal of colorectal adenomas provides evidence for risk stratification of patients at colonoscopic polypectomy.

Context The association of colorectal cancer (CRC) with pre-existing adenomatous polyps was challenged for decades until the National Polyp Study (NPS) demonstrated that colonoscopic polypectomy prevented deaths from CRC. In a follow-up of the Minnesota Colon Cancer Control study (46 551 participants), those randomly assigned to annual screening with a sensitive faecal occult blood test, sustained a 32% CRC mortality reduction over 30 years which was consistent with the effect of polypectomy. In the Nurses’ Health Study and the Health Professional Follow-up Study (88 902 participants followed over 22 years), lower endoscopy was associated with a 43% CRC mortality reduction compared to no endoscopy.