A breast cancer (BRCA) gene test is a blood test to check for changes (mutations) in genes called BRCA1 and BRCA2. This test can help you know your chance of getting breast cancer and ovarian cancer. A BRCA gene test does not test for cancer itself.
BRCA1 and BRCA2 are genes that help control normal cell growth. Sometimes, people inherit changes in one of these genes. These changes are called mutations. If you inherit a mutation in a BRCA (say "BRAH-kuh") gene, you have a greater risk of breast and ovarian cancers as well as some other cancers, such as prostate and pancreatic cancers.
You can inherit the gene changes from either your mother's or father's side of the family.
BRCA gene changes aren't common. Your doctor may talk to you about testing based on your family medical history or your personal medical history.
If you are concerned that you may have a BRCA gene change, talk with your doctor. You can have genetic testing to find out if you have the BRCA mutation. A test may look just for BRCA gene changes. Or you may have a multi-gene panel test that also looks for other genes that can raise your cancer risk.
There are some important things to keep in mind when you are thinking about having a BRCA gene test.
- A negative BRCA result does not guarantee that you will not get breast cancer. BRCA gene changes do increase the risk of breast cancer. But there are other gene changes that may cause cancer, too.
- Most provincial or private health plans will cover the cost of genetic testing if you meet the conditions for testing.
- You may worry that test results could affect your future employment options or the cost or availability of private insurance. In Canada, there is a law called the Genetic Non-Discrimination Act (GNA). It protects your genetic information.
It is very important to have genetic counselling both before and after this test. It can help you understand the benefits, risks, and possible outcomes of the test.
Why It Is Done
A BRCA gene test is done to find out if you have BRCA gene changes that increase your risk of breast, ovarian, and some other cancers.
You might consider this test if you or your family have certain health problems or risk factors. Examples include having one or more members of your family who've had breast, ovarian, prostate, or pancreatic cancer, being diagnosed with breast cancer before age 50, and having an Ashkenazi Jewish heritage.
You may feel better if the test shows that you don't have a BRCA mutation. If the test shows that you do have a BRCA mutation, you may be able to make some decisions that could reduce your cancer risk.
If you are concerned that you may have a BRCA gene change, talk with your doctor.
How To Prepare
The information from a BRCA gene test can have a deep impact on your life. So it's very important to get genetic counselling before you have this test. A genetic counsellor can talk with you about the test, what the results mean, and your medical and emotional concerns.
If you have a family member who has breast or ovarian cancer, you may want to ask that family member to have a gene test first. If your relative's test finds a changed BRCA gene, you and other family members can then be tested for that specific gene change. A genetic counsellor can talk with you about the test and what you might learn from it.
How It Is Done
A health professional uses a needle to take a blood sample, usually from the arm.
How It Feels
When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.
There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.
- A negative test may give you a false sense of security. So you may not have the regular tests that help find cancer at an early stage. But a negative BRCA test does not mean that you will never have breast or ovarian cancer.
- A positive test result may cause anxiety or depression. A positive BRCA test does not mean that you will definitely get breast or ovarian cancer.
- You may feel anxious or depressed if you learn that you have a high risk of cancer and could pass that risk on to your children. This information could also affect your relationship with your partner or other family members.
- You may worry that test results could affect your future employment options or the cost or availability of private insurance. Talk with your doctor about genetic privacy or visit the Office of the Privacy Commissioner of Canada webpage at www.priv.gc.ca for more information.
It may take several weeks to get the results of your test.
No changes were found in the BRCA1 or BRCA2 genes.
A negative result and your overall family risk must be considered together. If you have a strong family history of breast, ovarian, or some other cancers like pancreatic or prostate cancer, your cancer risk may be higher than normal even if you have a negative BRCA result.
BRCA1 or BRCA2 gene changes are present.
Your range of risk will depend on the type of genes you have and your personal and family history.
Uncertain (BRCA variant of uncertain significance, or VUS)
This result may mean that a BRCA gene change (other than BRCA1 or BRCA2) is present. Researchers don't know whether some BRCA gene changes increase the risk of cancer.
Current as of: September 8, 2021
Author: Healthwise Staff
Sarah Marshall MD - Family Medicine
E. Gregory Thompson MD - Internal Medicine
Kathleen Romito MD - Family Medicine
Elizabeth T. Russo MD - Internal Medicine
Wendy Y. Chen MD, MPH MD, MPH - Medical Oncology, Hematology
Current as of: September 8, 2021
Author: Healthwise Staff
Medical Review:Sarah Marshall MD - Family Medicine & E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Elizabeth T. Russo MD - Internal Medicine & Wendy Y. Chen MD, MPH MD, MPH - Medical Oncology, Hematology