Inherited mutations linked to colorectal cancer
Expert guidelines list who should consider genetic counseling and testing for an inherited mutation linked to cancer.
The most common genes associated with hereditary colorectal cancer are (click on the link for more information about each gene mutation):
There are other inherited mutations that increase the risk of colorectal cancer. Most of these are rare.
- Familial adenomatous polyposis (FAP) is caused by an inherited mutation in the APC gene. People with an inherited FAP mutation may develop 100s of polyps and they may be diagnosed with colorectal cancer at a young age.
- Inherited mutations in the MUTYH gene (also called MYH) are linked to a condition called MUTYH-associated polyposis (MAP). People must be born with two abnormal copies of the MUTYH gene (one from each of their parents) in order to develop this syndrome.
- Inherited mutations in the MEN1 and genes are linked to neuroendocrine cell cancers. This includes colorectal gastrointestinal carcinoid tumors.
- Other rare inherited mutations linked to colorectal cancer risk include:
Genetic counseling and testing for people diagnosed with colorectal or endometrial cancer
The National Comprehensive Cancer Network has guidelines on which people diagnosed with colorectal or endometrial cancer should undergo genetic counseling and testing. People diagnosed with colorectal cancer who have any of the following should speak with a genetics expert about genetic testing:
- A tumor test result suggesting an inherited mutation (for example, an MSI-H or tumor).
- A blood relative who tested positive for an inherited mutation linked to cancer.
- Colorectal or endometrial cancer diagnosed before age 50.
- Diagnosed with more than one cancer.
- A family history of one or more first or with any of the following types of cancer diagnosed before age 50 or two or more first or with any of the following cancers diagnosed at any age:
- small bowel
- biliary tract
- brain (usually glioblastoma)