A colorectal polyp is a growth that sticks out of the lining of the colon or rectum.

Polyps of the colon and rectum are usually benign and produce no symptoms, but they may cause painless rectal bleeding. There may be single or multiple polyps and they become more common as people age. Over time, certain types of polyps, called adenomatous polyps, may develop into cancer. Another common type of polyp found in the colon is called a hyperplastic polyp, which is generally not at risk for developing into colon cancer.

Polyps greater than one centimeter have a greater cancer risk associated with them than polyps under one centimeter. Risk factors include advancing age or a family history of colon cancer or polyps.

Polyps may also be associated with some hereditary disorders, including:

• Gardner's syndrome
• Peutz-Jeghers syndrome
• Juvenile polyposis
• Familial adenomatous polyposis
• Lynch syndrome (HNPCC)

There are usually no symptoms. However, the following symptoms may occur:

• Rectal bleeding
• Bloody stools
• Fatigue associated with anemia
• Abdominal pain (rare)

A rectal examination may reveal a polyp that can be felt by the physician. However, the physical exam is usually normal.

Tests that show polyps:

• Sigmoidoscopy
• Colonoscopy
• Virtual colonoscopy
• Barium enema