Familial adenomatous polyposis
Other Names for this Disease
- Adenomatous polyposis coli
- Adenomatous polyposis of the colon
- Familial adenomatous polyposis of the colon
- Familial intestinal polyposis
- Familial multiple polyposis
Your QuestionThe father of my children lost his life after a short battle with colon cancer. Several members of his family had various other types of cancer. I would like to help my children prevent the development of cancer. What are the symptoms of familial adenomatoous polyposis (FAP)? What steps can we take to be better prepared for this disease? Who can help us with this endeavor?
We have identified the following information that we hope you find helpful. If you still have questions, please contact us.
Questions on this page
- What is familial adenomatous polyposis (FAP)?
- What types of polyps are associated with familial adenomatous polyposis (FAP)?
- What other features may be present in familial adenomatous polypsis (FAP)?
- Can children have genetic testing for familial adenomatous polyposis (FAP)?
- How can I find a genetics professional in my area?
Gastric (stomach) polyps can be either fundic-gland or adenomatous. Gastric fundic-gland polyps are hamartomatous (characterized by growth of normal-appearing tissue that builds up into a noncancerous tumor which can form into cancer over time). They occur in approximately half of individuals with FAP, and are located in the fundus and body of the stomach. Although gastric fundic-gland polyps are considered to have little malignancy potential, several reports of gastric adenocarcinoma and high-grade dysplasia have been reported. Gastric adenomatous polyps occur in about 10% of individuals with FAP and are usually confined to the gastric antrum. The risk for gastric cancer is small.
Adenomatous polyps of the duodenum (small bowel) are observed in 50-90% of individuals with FAP, and are commonly found in the second and third portions of the duodenum. The lifetime risk of small bowel malignancy is 4-12%; the majority occur in the duodenum. Adenomatous polyps of the periampullary region (including the duodenal papilla and ampulla of Vater) are seen in at least 50% of individuals. Polyps in this area can cause obstruction of the pancreatic duct resulting in pancreatitis, which occurs at increased frequency in FAP. These polyps are often small and require a side-viewing endoscope for visualization. The risk of malignancy of polyps in the periampullary region is higher than that of adenomas in other parts of the duodenum. 
Adenomatous polyposis of the gallbladder has been reported in about 10 cases of FAP. These adenomatous gallbladder lesions are typically discovered late, often when the patient is older than 40. The pathogenesis of gallbladder adenomas is still unclear and it is difficult to assess the risk of malignancy.
Several extracolonic cancers (small bowel, stomach, pancreas, thyroid, central nervous system, liver, bile ducts, adrenal gland) occur with a higher incidence in individuals with FAP than in the general population as well.
Genetics clinics are a source of information for individuals and families regarding genetic conditions, treatment, inheritance, and genetic risks to other family members. More information about genetic consultations is available from Genetics Home Reference. To find a genetics clinic, we recommend that you contact your primary healthcare provider for a referral.
The following online resources can help you find a genetics professional in your community:
- GeneTests has a searchable directory of US and international genetics and prenatal diagnosis clinics.
- The National Society of Genetic Counselors provides a searchable directory of US and international genetic counseling services.
- The American College of Medical Genetics has a searchable database of US genetics clinics.
- The University of Kansas Medical Center provides a list of US and international genetic centers, clinics, and departments.
- The American Society of Human Genetics maintains a database of its members, which includes individuals who live outside of the United States. Visit the link to obtain a list of the geneticists in your country, some of whom may be researchers that do not provide medical care.
- Familial adenomatous polyposis. Genetics Home Reference Web site. April 2008; http://ghr.nlm.nih.gov/condition=familialadenomatouspolyposis. Accessed 4/6/2010.
- Randall W. Burt, Kory W. Jasperson . APC-Associated Polyposis Conditions. GeneReviews. 2008; http://www.ncbi.nlm.nih.gov/books/NBK1345/. Accessed 9/2/2011.
- Brevet M, Brehant O, Dumont F, Regimbeau JM, Dupas JL, Chatelain D. Gastroenterol Clin Biol. April 2007; http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=DetailsSearch&Term=17483782%5Buid%5D. Accessed 4/6/2010.