FAP is a genetic abnormality that results in the development of hundreds to thousands of polyps in the gastrointestinal tract (both upper and lower). Untreated, all of these polyps eventually progress to cancer. It is a rare cause of cancer overall, representing only 1 percent of colon cancer patients. It may be passed on from your parents (affecting 50 percent of offspring of affected parents) or develop from a new mutation. If detected early, it can be treated easily. Affected individuals may also develop stomach or small intestine polyps and other issues. Any affected patients are encouraged to see a genetics counselor.