The majority of colon cancer patients do not have a family history or genetic connection to the disease. This is when the cancer occurs by chance, and is often called “sporadic cancer.”
However, in some families, we see more cancer than we would expect. About 1 in 4 patients have a family history of colon cancer that could suggest a genetic and/or hereditary factor. A family history of colon cancer, that is, an immediate family member (parent, brother, sister) or multiple family members with colon cancer or polyps, puts you at an increased risk for the disease.
If you have a family history, you may need to be screened at age 40, or 10 years before the youngest case in your immediate family, whichever is earlier.
What’s your genetic risk? Take our quiz and find out!
When Should I Get Tested?
If you have a family history of colon cancer, there are a number of genetic tests to find out if your cancer is hereditary, that is, caused by a genetic mutation passed down through the family. Your doctor can help you understand your individual cancer risk and which type of genetic tests, if any, may be useful for you or for other members of your family.
The most common types of hereditary colon cancer are familial adenomatous polyposis (FAP) and Lynch syndrome, also known as hereditary nonpolyposis colon cancer (HNPCC).
What’s My Risk
It Runs in the Family:
Colon Cancer & Genetics