FAP syndrome
Familial adenomatous polyposis (FAP) is an inherited disorder sometimes found in people with colorectal cancer.
People with FAP may develop noncancerous (benign) colon polyps as early as their teenage years.
What is FAP: the facts
- Familial adenomatous polyposis (FAP) is an inherited disorder sometimes found in people with colorectal cancer.
- Approximately two percent of all colon cancer could be caused by a hereditary adenomatous polyposis condition.
- People with the classic type of FAP may develop noncancerous (benign) colon polyps as early as their teenage years.
- Screening usually begins at eight to ten years old.
- The type of polyp most often seen in FAP syndrome, called an adenoma, is precancerous.
- The average age at which an individual with FAP develops colorectal cancer is 39 years old.
- Some people have a variation of the disorder, called attenuated familial adenomatous polyposis (AFAP), with fewer polyps.
- The average age of colon cancer onset for those with AFAP is 55 years.
- People with FAP can also develop noncancerous growths called desmoid tumors which are noncancerous (benign) tumors that typically develop in the arms, legs, abdomen.
Other tumors in the body
In both classic FAP and AFAP, benign and cancerous tumors are sometimes found in other places in the body, including the small intestine, stomach, bones, skin, and other tissues. People who have colon polyps outside the colon are sometimes described as having Gardner syndrome.
FAP: Causes, risks, prediction, and screening
Genetics and your risk of colon cancer
About five to seven percent of colon cancer patients have inherited a gene mutation that puts them at higher risk of developing colorectal cancer. Knowing your family history is an important part of prevention.
Blog: Are you at high risk for colon cancer?
Having any inherited risk factors on your radar early will allow you to be your own advocate and be proactive about your health and screenings. Learn about what you can and cannot control in terms of risk, such as diet, age, lifestyle, and ethnicity.
We are here for you
Facing FAP syndrome or other inherited risks can make you feel isolated. Find allies in our online communities, our Buddy Program, one-on-one support from our live navigators, and much more. You are not alone.
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