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Overview of colon polyps

Finlay A Macrae, MD
Section Editor
Paul Rutgeerts, MD, PhD, FRCP
Deputy Editor
Shilpa Grover, MD, MPH, AGAF


A polyp of the colon refers to a protuberance into the lumen above the surrounding colonic mucosa. Colon polyps are usually asymptomatic but may ulcerate and bleed, cause tenesmus if in the rectum, and, when very large, produce intestinal obstruction. Colonic polyps may be neoplastic (eg, adenomas) or non-neoplastic (eg, inflammatory polyps).

This topic will review the clinical features and management of colonic polyps and polypoid lesions of the colon. Colorectal cancer screening and surveillance after colorectal cancer resection are discussed separately. (See "Screening for colorectal cancer: Strategies in patients at average risk" and "Screening for colorectal cancer in patients with a family history of colorectal cancer" and "Surveillance after colorectal cancer resection" and "Clinical manifestations and diagnosis of familial adenomatous polyposis" and "MUTYH-associated polyposis" and "Peutz-Jeghers syndrome: Epidemiology, clinical manifestations, and diagnosis".)


Inflammatory polyps are non-neoplastic intraluminal projections of mucosa consisting of stromal and epithelial components and inflammatory cells. Inflammatory polyps include inflammatory pseudopolyps, prolapse type inflammatory polyps, and myoglandular polyps.

Inflammatory pseudopolyps — Inflammatory pseudopolyps are irregularly shaped islands of residual intact colonic mucosa that are the result of the mucosal ulceration and regeneration that occurs in response to localized or diffuse inflammation (eg, ulcerative colitis or Crohn disease).

Endoscopic features and histology – Inflammatory polyps may be pedunculated or sessile and are usually smaller than 2 cm. Inflammatory pseudopolyps in patients with inflammatory bowel disease are typically multiple, often filiform, and scattered throughout the involved areas of the colon. They may also be more isolated and semipedunculated in areas of recent inflammation, and have mucus adherent to their apices (picture 1). Inflammatory pseudopolyps are composed of a mixture of inflamed lamina propria and distorted colonic epithelium; surface erosions may or may not be present.

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Literature review current through: Nov 2017. | This topic last updated: Nov 14, 2017.
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