- Familial Adenomatous Polyposis (Gardner's Syndrome) Center
- Take the Tummy Trouble Quiz
- Boost Digestive Health
- Digestive Distress Slideshow: Problem Foods to Avoid
- Patient Comments: Gardner's Syndrome - Share Your Experience
- Patient Comments: Gardner's Syndrome - Symptoms
- Find a local Gastroenterologist in your town
- What is familial adenomatous polyposis?
- How common is familial adenomatous polyposis?
- What genes are related to familial adenomatous polyposis?
- How do people inherit familial adenomatous polyposis?
- Where can I find information about treatment for familial adenomatous polyposis?
- What other names do people use for familial adenomatous polyposis?
What is familial adenomatous polyposis?
Familial adenomatous polyposis (FAP) is an inherited disorder characterized by cancer of the large intestine (colon) and rectum. People with the classic type of familial adenomatous polyposis may begin to develop multiple noncancerous (benign) growths (polyps) in the colon as early as their teenage years. Unless the colon is removed, these polyps will become malignant (cancerous). The average age at which an individual develops colon cancer in classic familial adenomatous polyposis is 39 years. Some people have a variant of the disorder, called attenuated familial adenomatous polyposis, in which polyp growth is delayed. The average age of colorectal cancer onset for attenuated familial adenomatous polyposis is 55 years.
In people with classic familial adenomatous polyposis, the number of polyps increases with age, and hundreds to thousands of polyps can develop in the colon. Also of particular significance are noncancerous growths called desmoid tumors. These fibrous tumors usually occur in the tissue covering the intestines and may be provoked by surgery to remove the colon. Desmoid tumors tend to recur after they are surgically removed. In both classic familial adenomatous polyposis and its attenuated variant, benign and malignant tumors are sometimes found in other places in the body, including the duodenum (a section of the small intestine), stomach, bones, skin, and other tissues. People who have colon polyps as well as growths outside the colon are sometimes described as having Gardner syndrome.
A milder type of familial adenomatous polyposis, called autosomal recessive familial adenomatous polyposis, has also been identified. People with the autosomal recessive type of this disorder have fewer polyps than those with the classic type. Fewer than 100 polyps typically develop, rather than hundreds or thousands. The autosomal recessive type of this disorder is caused by mutations in a different gene than the classic and attenuated types of familial adenomatous polyposis.
Quick GuideDigestive Disorders: Common Misconceptions
How common is familial adenomatous polyposis?
The reported incidence of familial adenomatous polyposis varies from 1 in 7,000 to 1 in 22,000 individuals.
What genes are related to familial adenomatous polyposis?
Mutations in the APC gene cause both classic and attenuated familial adenomatous polyposis. These mutations affect the ability of the cell to maintain normal growth and function. Cell overgrowth resulting from mutations in the APC gene leads to the colon polyps seen in familial adenomatous polyposis. Although most people with mutations in the APC gene will develop colorectal cancer, the number of polyps and the time frame in which they become malignant depend on the location of the mutation in the gene.
Mutations in the MUTYH gene cause autosomal recessive familial adenomatous polyposis (also called MYH-associated polyposis). Mutations in this gene prevent cells from correcting mistakes that are made when DNA is copied (DNA replication) in preparation for cell division. As these mistakes build up in a person's DNA, the likelihood of cell overgrowth increases, leading to colon polyps and the possibility of colon cancer.
How do people inherit familial adenomatous polyposis?
Familial adenomatous polyposis can have different inheritance patterns.
When familial adenomatous polyposis results from mutations in the APC gene, it is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition.
When familial adenomatous polyposis results from mutations in the MUTYH gene, it is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition.
Where can I find information about treatment for familial adenomatous polyposis?
These resources address the management of familial adenomatous polyposis and may include treatment providers.
What other names do people use for familial adenomatous polyposis?
- Adenomatous Polyposis Coli
- Adenomatous Polyposis of the Colon
- Familial Intestinal Polyposis
- Familial Multiple Polyposis
Multiple Polyposis Syndrome
- Familial Polyposis Coli
- Familial Polyposis Syndrome
- Hereditary Polyposis Coli
- Polyposis Coli
SOURCE: Genetics Home Reference, National Institutes of Health
Quick GuideDigestive Disorders: Common Misconceptions
Daily Health News
Digestive Disorders Resources
Subscribe to MedicineNet's General Health Newsletter
Gardner's Syndrome - Share Your Experience
Have you been diagnosed with adenomatous polyposis? Please share your experience with Gardner's syndrome.Post View 6 Comments
Gardner's Syndrome - Symptoms
What were your symptoms associated with Gardner's Syndrome? What kinds of tests or procedures have you received?Post View 1 Comment
Top Gardner Syndrome Related Articles
CancerCancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.
Cancer CausesThough it's difficult to say why some people develop cancer while others don't, research shows that certain risk factors increase a person's odds of developing cancer. These risk factors include growing older, family history of cancer, diet, alcohol and tobacco use, and exposure to sunlight, ionizing radiation, certain chemicals, and some viruses and bacteria.
Cancer DetectionCancer detection are methods used to find cancer in persons who may or may not have symptoms. Symptoms of cancer are abnormal sensations or conditions that persons can notice that are a result of the cancer. It is important to your doctor for regular checkups and not wait for problems to occur.
Colon CancerColon cancer is a malignancy that arises from the inner lining of the colon. Most, if not all, of these cancers develop from colonic polyps. Removal of these precancerous polyps can prevent colon cancer.
Colon Cancer PreventionColo-rectal cancer is both curable and preventable if it is detected early and completely removed before the cancerous cells metastasize to other parts of the body. Colonoscopy and flexible sigmoidoscopy (along with digital rectal examination and stool occult blood testing) are both effective at preventing colo-rectal cancers and detecting early colo-rectal cancers.
Colon Cancer ScreeningColon cancer is preventable by removing precancerous colon polyps, and it is curable if early cancer is surgically removed before cancer spreads to other parts of the body. Therefore, if screening and surveillance programs were practiced universally, there would be a major reduction in the incidence and mortality of colorectal cancer.
ColonoscopyA colonoscopy is a procedure whereby a physician inserts a viewing tube (colonoscope) into the rectum for the purpose of inspecting the colon. Colonoscopy is the best method currently available to diagnose, detect, and treat abnormalities within the colon.
Genetic CounselingYour health care provider may refer you to a genetic professional. Universities and medical centers also often have affiliated genetic professionals, or can provide referrals to a genetic professional or genetics clinic. Genetic counseling provides patients and family members the tools to make the right choice in regard to test for a disease or condition.
Genetic DiseaseThe definition of a genetic disease is a disorder or condition caused by abnormalities in a person's genome. Some types of genetic inheritance include single inheritance, including:
- cystic fibrosis,
- sickle cell anemia,
- Marfan syndrome,
- and hemochromatosis.