Genetics and inherited conditions

About 5-7% of colorectal cancer patients inherited a gene mutation that greatly increased their lifetime risk.

Genetics and your risk

What if you had a crystal ball that told whether you and your family are more likely to face colorectal cancer?

Unfortunately, we don’t have a crystal ball — or its medical equivalent — quite yet, but knowing about your family history and any hereditary genetic conditions can help you stay ahead of the game.

Cancer & genetics

- While there remains much to learn about this disease, we know it is caused by gene mutations, or changes, that result in cells growing out of control.
- As you age, genemutations accumulate, and this is why colorectal cancer most often happens in people over age 50. In most cases, the gene mutations leading to cancer happen randomly, although they can be helped along by carcinogens, like the chemicals in cigarette smoke.
- About 25 percent of cases patients have a family history of the disease, signaling a possible condition that increases the likelihood of colorectal cancer at a younger age.
- In certain individuals, genetic mutations that increase the risk of cancer can be inherited from parents.
- Inherited genetic mutations play a role in five to ten percent of all cancer cases, as well as colorectal cancer.
- Researchers have found more than 50 hereditary cancer syndromes overall. Fortunately, a number of these inherited conditions can beidentified through genetic testing and the results can be lifesaving.
Talk to your doctor about being genetic testing. These tests:
- Can find gene mutations linked to inherited syndromes.
- Are typically conducted with either a blood or saliva draw.

young person caring for an older individual

Genetic conditions associated with colorectal cancer

The most common types of hereditary colorectal cancer are:

Lynch syndrome
Muir-Torre syndrome (MTS)
MUTYH-associated polyposis syndrome (MAP syndrome)
Familial adenomatous polyposis (FAP)
Peutz-Jeghers syndrome
Li-Fraumeni Syndrome

How do I know if I’m at risk?

There are three subgroups of risk for cancer.

Sporadic risk

If you fall into the sporadic group, which means you have no family history of cancer or inherited genetic predisposition, you have about a one in 24 chance of getting colorectal cancer.

Familial risk

If you have familial risk, meaning an immediate family member has the disease, your lifetime risk increases to 10 to 20 percent.

Hereditary risk

Those who have the highest lifetime risk of colorectal cancer are in the hereditary subgroup. Depending on the particular genetic syndrome, the chances of getting colorectal cancer may be 30 to 100 percent.

What can I do after I know my genetic risk?

Screening is the most important thing you can do to prevent colorectal cancer because it finds cancer in the early stages. Talk to your healthcare provider about your personal genetic risks.

Screening & prevention

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Genetics and inherited conditions

Genetics and your risk

Cancer & genetics

Genetic conditions associated with colorectal cancer