Familial adenomatous polyposis (FAP) is the most common adenomatous polyposis syndrome. It is an autosomal dominant inherited disorder characterized by the early onset of hundreds to thousand s of adenomatous polyps throughout the colon. If left untreated, all patients with this syndrome will develop colon cancer by age 35-40 years.
• Noncancerous bone tumors
Medical care is mainly based on endoscopic surveillance to detect the onset of polyposis. Consequently, surgery would prevent the development of colon cancer. However, in view of the increased risk for the development of other cancers, continued medical follow-up is required with a number of surveillance tests, as colectomy would only address the potential risk of colon cancer.
Approximately 1 in 10,000 babies born live will have FAP resulting from a germline adenomatous polyposis coli (APC) mutation. Because this is an autosomal-dominant condition, males and females are equally affected by this disease. There do not appear to be significant racial, ethnic, or geographical differences in the incidence of FAP, nor do environmental factors appear to affect the disease incidence. Up to 30% of FAP probands have no family history of polyposis and presumably these people have spontaneous mutations in APC. Only 1% of all colorectal cancer is secondary to FAP.