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Attenuated familial adenomatous polyposis

Other Names for this Disease
  • AAPC
  • AFAP
  • Attenuated adenomatous polyposis coli
  • Attenuated familial polyposis coli
  • Attenuated FAP
More Names
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What is attenuated familial adenomatous polyposis?

How might attenuated familial adenomatous polyposis be treated?

What is attenuated familial adenomatous polyposis?

Attenuated familial adenomatous polyposis (AFAP) is a cancer predisposition syndrome characterized by a significant risk to develop colon cancer. Individuals with AFAP generally have fewer colon polyps (an average of 30) than in classic FAP, and the polyps tend to occur more proximally in the colon. The average age of colon cancer diagnosis in affected individuals is 50 to 55 years, which is 10 to 15 years later than in those with classic FAP, but earlier than when colon cancer occurs in the general population. In addition to colon polyps, findings may include upper gastrointestinal polyps and cancers; non-intestine related signs of FAP (but CHRPE and desmoid tumors are rare); and thyroid cancer. AFAP is caused by mutations in the APC gene and is inherited in an autosomal dominant manner.[1]
Last updated: 12/16/2011

How might attenuated familial adenomatous polyposis be treated?

Management of AFAP is generally based on continued surveillance to detect if and when the formation of polyps occurs.[2] Screening by colonoscopy and endoscopy has been recommended for affected individuals starting at the age of 20 to 25 years. Individuals with polyps may undergo polypectomy (removal of polyps), followed by continued yearly surveillance. Individuals with too many adenomas to remove during endoscopy, or those who cannot undergo surveillance, may consider a prophylactic colectomy (removal of all or part of the colon).[3] About one third of individuals with AFAP have few enough colon polyps that surveillance with periodic polypectomy is sufficient.[1] Because individuals with AFAP can also develop duodenal adenomas and other cancers, upper endoscopy is typically recommended starting at age 20 to 30 years and then every one to three years, depending on the number of polyps. There is currently no consensus on screening for tumors that occur outside of the colon, so it has been suggested that affected individuals are managed as if they have classic FAP.[3] A number of drugs such as celecoxib and sulindac reportedly have been successful at reducing the number and the size of polyps in affected individuals, but these drugs generally help to prevent further complications and are not considered sufficient treatment.[2]

Additional and more detailed information about the treatment and management of FAP, including AFAP, is available on eMedicine's Web site and can be viewed by clicking here.
Last updated: 12/16/2011

  1. Jasperson KW, Burt RW. APC-Associated Polyposis Conditions. GeneReviews. October 27, 2011; Accessed 2/17/2012.
  2. Mohammad Wehbi. Familial Adenomatous Polyposis. eMedicine. September 1, 2011; Accessed 12/16/2011.
  3. Peter A L Bonis, Dennis J Ahnen, Lisen Axell. Familial adenomatous polyposis and MUTYH associated polyposis: Screening and management of patients and families. UpToDate. Waltham, MA: UpToDate; 2011;