Genetics and Colorectal Cancer

Does colorectal cancer run in families?

About 20% (or 1 in 5 cases) of colorectal cancer
may have a familial or hereditary basis.
At USC/Norris’ Colorectal Center our
certified genetic counselor is available
to meet with patients who want to know if colorectal cancer
may run in their families.
The genetic counselor can assess their genetic risks and discuss
options for genetic testing.

How do you know if colorectal
cancer runs in my family?

We are more likely to suspect that colorectal cancer
runs in the family when we observe one or more of the following:

• Colorectal cancer diagnosed before age 50
• More than one person with colorectal cancer on the
same side of the family
• Colorectal and uterine cancer on the same side of the family
• A history of multiple polyps in the colon
• Ashkenazi Jewish (Eastern European Jewish) ancestry
in a person with a history of colorectal cancer or polyps

Anyone who has concerns or questions about their family history
of cancer, or about the risk of cancer in their relatives can
benefit from having genetic counseling. Some people go on
to have genetic testing (usually done through a blood test)
to help define their risk.

What is Genetic Counseling?

Genetic counseling for familial cancer risk involves the following:
• Collection and interpretation of your family and medical
history
• Talking about the likelihood of carrying a genetic change
that makes a person more prone to colorectal cancer
• Discussion of the pros and cons of genetic testing for
familial cancer risk
• Ordering and interpretation of genetic tests for
familial colorectal cancer
• Discussion of medical options to help reduce cancer risks
• Addressing the psychological implications of familial
cancer risks

Genetic counseling for cancer risk can help you and your family members make informed decisions about when and how
often cancer screening tests should be done.

How can I get an appointment for
Genetic Counseling?

• Call 323-865-0800 for appointments or if you want more information.