[Colorectal polyps]

Abstract

Background: Colorectal polyps are common, but there is a large geographical variation--and Norway has one of the highest incidences. There is circumstantial evidence that most cancers develop from polyps; so detection, eradication and follow-up stategies for polyps are important. The article provides an update on these topics.

Material and methods: The article is based on the authors' own research and clinical experience, and on literature retrieved through a non-systematic search of Pubmed.

Results and interpretation: Classification of polyps is based on morphology and histology, and the risk of malignancy depends on both. Colonoscopy is the primary method for detection of polyps; biopsies can be taken and treatment initiated during the procedure. CT colography (virtual colonoscopy) may be on the verge of becoming a diagnostic tool. Pedunculated polyps are usually removed by endoscopical snare resection, which is sufficient even when cancer has developed in the head of the polyp. Large sessile polyps, with considerable risk of malignancy, may be removed by transanal endoscopic microsurgery in the rectum, while surgical localised resection will often be required in the colon. Between these extremes, many polyps may be removed by more advanced endoscopic techniques, and at times with supplementary ablation.