Colorectal polyps are abnormal overgrowths of tissue that occur in the large bowel. There are a number of different types of colorectal polyp, some of which have the potential to develop into colorectal cancer.
Most polyps arise in an otherwise normal colon, and their likelihood of being present increases with age. However, there are a number of conditions (polyposis syndromes) that occur due to inherited genetic changes and result in the development of multiple polyps at a younger age.
Colorectal polyps are usually asymptomatic, and are commonly found incidentally during a test to investigate a bowel-related symptom. However, sometimes polyps may present with rectal bleeding, excess mucous production or a change in bowel habit, usually to looser motions.
Colorectal polyps are often detected during a camera test of the large bowel (either a flexible sigmoidoscopy or colonoscopy), and can usually be removed using endoscopic techniques. It is recommended that, following removal, the colonoscopy be repeated at a set time interval to check for re-growth of further polyps. Occasionally, polyps are so large that they cannot be removed endoscopically and surgical resection is necessary; this is uncommon. Surgery is also indicated for patients with polyposis syndromes in view of the elevated risk of cancer development.