Update: Testing for the Breast Cancer Gene

By Jane Farrell

Should you be tested to see if you have the breast-cancer gene? Here, experts from the federal Centers for Disease Control tell you what you need to know:

Each year, over 200,000 women in the United States are diagnosed with breast cancer and more than 20,000 are diagnosed with ovarian cancer. About 3% of breast cancers (about 6,000 women per year) and 10% of ovarian cancers (about 2,000 women per year) result from inherited mutations (changes) in the BRCA1 and BRCA2 genes that are passed on in families. Knowing your family health history can help you find out if you could be at higher risk of developing breast and/or ovarian cancer. If so, you can take steps to help lower your risk.

You might be at increased risk of having an inherited mutation in the BRCA1 or BRCA2 genes if your family health history includes one or more of the following:

Several close relatives with either breast or ovarian cancer.

One or more close relatives with breast cancer at a younger age (before age 50).

A close relative with cancer of both breasts.

A close relative who had both breast and ovarian cancer.

A close male relative with breast cancer.

Ashkenazi Jewish (Eastern European) ancestry plus one or more close relative with breast or ovarian cancer.

A close relative with a known BRCA1 or BRCA2 mutation.

All women should collect and record their family health history of breast and ovarian cancer. You can inherit BRCA mutations from your mother or your father, so be sure to include information from both sides of your family. Close relatives include your mother, sister(s), daughter(s), grandmothers, aunt(s), niece(s), and granddaughter(s); and similarly for any male relatives with breast cancer.

You can use the Know:BRCA tool https://www.knowbrca.org/ to collect your family health history information, assess your risk for BRCA mutations, and share this information with your doctor. Update your family health history on a regular basis and let your doctor know if more cases of breast or ovarian cancer occur.

If you are concerned that your family health history means that you might have an inherited mutation in your BRCA1 or BRCA2 genes, the first step is to talk to your doctor about your family health history to learn whether genetic counseling might be right for you. Your doctor may refer you to a genetic counselor or other qualified health care professional to discuss your family health history and to learn about your options for genetic testing.

The genetic counselor will ask questions about breast and ovarian cancer in your family that may include:

Which of your close biological relatives had breast or ovarian cancer?

What age was each of these relatives when the cancer was diagnosed?

Did any of these relatives have cancer in both breasts, or have both breast and ovarian cancer?

Have any of your close male relatives had breast cancer?

Where did your ancestors come from?

The genetic counselor can use your family health history information to determine your possible cancer risks and whether you might benefit from BRCA genetic testing to find out if you inherited a mutation in your BRCA1 or BRCA2 gene. However, most breast and ovarian cancer is not caused by these genetic mutations, so most women don’t need BRCA genetic testing.

Genetic testing is most useful if first performed on someone in your family who has had breast or ovarian cancer. If this relative has a BRCA1 or BRCA2 mutation, then her close relatives can be offered testing for that mutation. If she does not have a BRCA1 or BRCA2 mutation, then her relatives may not need to be tested. The genetic counselor can discuss the pros and cons of testing and what possible test results could mean for you and your family. It is important to note that genetic testing for BRCA mutations will not find all causes of hereditary breast or ovarian cancer. Health insurance often, but not always, covers the cost of genetic counseling and BRCA testing.

For more information on counseling, visit http://www.cdc.gov/genomics/resources/diseases/breast_ovarian_cancer/counseling.htm.

This report originally appeared on http://www.cdc.gov/features/hereditarycancer/.