Familial adenomatous polyposis, is an inherited colorectal cancer syndrome that can be passed from one generation to the next by a specific error or mutation in the genetic code of the APC gene. Virtually everyone that carries a mutation of the APC gene will eventually develop cancer in the lower part of the digestive system, including the large intestine (colon) and rectum.
This disease can become active in childhood with the development of adenomatous polyps causing bleeding with bowel movements, diarrhea, or abdominal pain usually in the mid teenage years however, exceptions are the rule. Colon adenomas can progress to cancer without causing apparent symptoms and can be silent killers. The average age for colon cancer is about 39 years. However, colon cancer can develop during the teen years and can develop in the absence of digestive problems.
Some people have a variant of the disorder, called attenuated familial adenomatous polyposis, in which adenomas are fewer in number and develop later in life, yet these patients also have significant risk of colorectal cancer but at a later average age of about 55 years. Surgery can reduce the colon cancer risk and is currently the best therapy for this disease. Patients with FAP are at risk for cancers and tumor growths elsewhere in the digestive tract and body.
Close follow-up with regular checkups is an important way to avoid further complications from this disease.