Symptoms
Most polyps don't cause symptoms. When there are symptoms, rectal bleeding is the most common complaint. Cramps, abdominal pain, or a blockage may occur. Occasionally, a polyp on a long stalk may fall through the anus.
Causes and Risk Factors
About 24 percent of patients who have cancer of the large bowel will also have polyps.
A condition called familial polyposis, in which 100 or more polyps carpet the colon and rectum, is genetic and results from a genetic mutation.
Rectal polyps can be felt during an examination by a doctor. Most often they are discovered when a patient undergoes endoscopy. Because rectal polyps are often multiple and may be present with cancer, a complete colonoscopy is necessary. Polyps can also be diagnosed using barium enema X-rays or double-contrast (pneumocolon) examination.