What is familial adenomatous polyposis (FAP)?

Familial adenomatous polyposis (FAP) leads to the growth of hundreds to thousands of non-cancerous (benign) polyps in the colon and rectum. Overtime, the polyps can become cancerous (malignant), leading to colorectal cancer at an average age of 39 years.

How is familial adenomatous polyposis diagnosed?

Sometimes a person may have a gene variant for an autosomal dominant condition and show no signs or symptoms of the condition. Familial adenomatous polyposis (FAP) is diagnosed based on the symptoms, clinical examination, and may be confirmed by the results of genetic testing.

What are the APAC-associated polyposis conditions?

APC-associated polyposis conditions include: familial adenomatous polyposis (FAP), attenuated FAP, and gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS). FAP is a colon cancer predisposition syndrome in which hundreds to thousands of adenomatous colonic polyps develop, beginning, on average, at age 16 years (range 7-36 years).

What is attenuated familialadenomatous polyposis (AFAP)?

Attenuated familialadenomatous polyposis (AFAP)is an inheritedcondition that increases the chance to develop cancerof the large intestine (colon) and rectum.

What causes adenomatous polyposis coli?

Overview. Familial adenomatous polyposis (FAP) is a rare, inherited condition caused by a defect in the adenomatous polyposis coli (APC) gene. Most people inherit the gene from a parent. But for 25 to 30 percent of people, the genetic mutation occurs spontaneously. FAP causes extra tissue (polyps) to form in your large intestine (colon) and rectum.

What are the possible complications of adenomatous polyposis?

In addition to colon cancer, familial adenomatous polyposis can cause other complications: Duodenal polyps. Periampullary polyps. Gastric fundic polyps. Desmoids. Other cancers. Noncancerous (benign) skin tumors. Benign bone growths (osteomas). Congenital hypertrophy of the retinal pigment epithelium (CHRPE). Dental abnormalities.