Gardner syndrome is a specific type of familial adenomatous polyposis (FAP), a genetic condition that causes growths (polyps) in the large intestine (colon) and rectum that become cancerous over time. Like all forms of FAP, Gardner syndrome also causes polyps to form in these areas. However, in addition to the polyps that form in the colon and rectum, individuals with Gardner syndrome are also at risk of developing both cancerous and noncancerous (benign) tumors in other areas of the body. These tumors tend to develop as fluid filled sacs (cysts) in the skin (called sebaceous and epidermoid cysts) or in bone (called osteomas). Other symptoms of Gardner syndrome may include too many teeth and a benign abnormality of the back of the eye (retina), called retinal pigment epithelial hypertrophy.
Gardner syndrome is caused by a change (mutation) in a gene affecting cell growth, called APC. This gene, when mutated, causes abnormal cell growth and division, which can lead to the creation of polyps and tumors. Gardner syndrome is inherited in a dominant manner, meaning a mutation in only one of the two APC gene copies a person has causes the condition. Each child of a person with Gardner syndrome has a 50% of also having Gardner syndrome.
Gardner syndrome is considered in a person with multiple polyps in their colon, along with other tumors or cysts in other parts of their body. The diagnosis is confirmed with genetic testing. Treatments include close monitoring and screening for colon polyps using a camera that is inserted into the colon (colonoscopy), removal of the polyps, and removal of the colon. If you or your child has been diagnosed with Gardner syndrome, talk to a doctor about all treatment options. Support groups are also available to connect with others who are affected by Gardner syndrome.