Colon Polyps

Types

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Hyperplastic polyps occur more often in the left (descending) colon and rectum and are usually less than a quarter-inch in diameter. ("Hyperplastic" refers to an increase in cells.)

Adenomatous polyps (sometimes referred to as adenomas) are divided into three subtypes based on their microscopic features: villous (hairy), tubular and tubulovillous. Villous adenomas tend to be larger than the other types and are more likely to become cancerous.

In general, the larger the polyp, the more likely it is to become cancerous.

The shapes of polyps are described as pedunculated or sessile. Pedunculated polyps grow on fleshy stalks and resemble mushrooms or toes, while sessile polyps have broad bases.

An individual may have a couple of polyps, or, in the case of familial adenomatous polyposis (FAP), a hereditary polyp disorder, it could be hundreds or even thousands.

Inflammatory polyps are occasionally found in the colon. These usually result from ulcerative colitis and are not a cancer risk, though having ulcerative colitis can increase an individual's risk for colon cancer.