Genetic testing gives people the chance to learn if their family history of breast cancer is due to an inherited gene mutation, such as a BRCA1 or BRCA2 mutation.
Only five to 10 percent of breast cancers in the United States are linked to an inherited genetic mutation [4-5]. For those who carry these mutations, the risk of breast cancer is greatly increased. However, there are steps people can take to try and decrease this risk.
Learn more about BRCA1 and BRCA2 mutations and breast cancer risk.
Who should consider testing?
Genetic testing for BRCA1 and BRCA2 is marketed as BRCAnalysis®. Although it is widely advertised, genetic testing is only recommended for certain people, including those with:
- A strong family history of breast cancer at an early age
- A family history of breast and ovarian cancers
- A family history of male breast cancer
- Ashkenazi Jewish heritage (who also have a family history of breast or ovarian cancer)
- A personal history of breast cancer at an early age
If you or an immediate family member is the only person in your family with breast cancer, it is unlikely that your family carries a BRCA mutation.
Weighing the risks and benefits of BRCA testing
Although BRCA testing requires just a blood sample, the risks and benefits should be considered before being tested. There are potential physical, emotional and financial impacts of knowing your genetic status. Thus, testing for the BRCA mutation is recommended only for people who fall into one of the categories listed above.
A health care provider or genetic counselor can talk with you about the issues related to genetic testing (more on these issues). For more information on genetic counseling, visit the National Cancer Institute’s website (or call its hotline at 1-800-4-CANCER) or the National Society of Genetic Counselors’ website.
Testing for BRCA mutations
In most cases, testing is first done on the family member with breast cancer. If no mutation is found, the cancer was probably not due to a genetic mutation and there is no need to test other family members. If a mutation is found, other family members can be tested for the specific BRCA mutation that was found. If all family members with breast cancer or ovarian cancer are deceased, a genetic counselor can help you decide whether it is appropriate to have genetic testing.
Testing for other gene mutations
Of the genes linked with breast cancer, BRCA1/2 mutations are the most well-known. Inherited mutations in the genes p53 and PTEN/ MMAC1 also increase breast cancer risk. Other genes are being studied for their possible role in breast cancer risk. Testing exists for some of these mutations, but is not often done because the mutations are much rarer than those in BRCA1/2 genes. If all family members with breast cancer or ovarian cancer are deceased, a genetic counselor can help you decide whether it is appropriate to have genetic testing.
BRCA genetic test results
Results from a BRCA test show whether there is a mutation related to cancer in the BRCA1/2 genes. There are three possible results:
- No mutation (negative)
- A mutation linked to cancer (positive or carrier)
- A mutation not currently known to increase breast cancer risk (called a variant of uncertain significance)
Having a BRCA1/2 mutation does not mean you are going to get breast cancer. And, not having a mutation does not mean you will never get breast cancer; you are still at risk.
If you have a BRCA1/2 mutation, there are steps you can take to lower your risk of breast cancer. You should discuss these steps with your health care provider. No matter your mutation status, there are things you can do that may lower your breast cancer risk. Learn more about a healthy lifestyle.
Risks of BRCA genetic testing
Psychological/emotional risks
If you are thinking about genetic testing, consider the emotional impact of the test results. For some people, knowing they carry a mutation can cause a lot of worry and anxiety even though they may never get breast cancer. For others, knowing they do not have a mutation may give a false sense of security of not being at risk. And, having a variant of uncertain significance (and not knowing whether the mutation increases risk) may add to the stress of an already trying process.
No matter the test result, it is important to follow breast cancer screening guidelines. There are special guidelines for women with a BRCA1/2 mutation and for those with no genetic mutations but with other factors that greatly increase risk. Talking with a genetic counselor or health care provider can help you understand your risk of breast cancer and make a breast health plan.
Emotional risks for family members
Genetic testing may also have an emotional impact on family members. For some people, finding out about a BRCA1/2 mutation may affect their siblings and children, possibly causing them worry and anxiety.
Other risks of genetic testing
Genetic testing should be private. There are state and federal laws to protect against genetic discrimination. The Genetic Information Nondiscrimination Act (GINA) went into effect in 2009. GINA prevents health insurers (but not life insurance or disability insurance) from denying coverage or charging higher premiums when a person's genetic profile puts them at higher risk for certain health conditions. GINA also protects against genetic discrimination from employers.
There have been no court cases of genetic discrimination regarding the BRCA1 and BRCA2 gene mutations since these tests have been used.
Benefits of BRCA genetic testing
Risk-lowering options
The results of a genetic test can help you make a personalized breast care plan. If there is a mutation, you may reduce your chances of getting breast cancer by:
Learn more about options for women at high risk.
Breast cancer screening for BRCA carriers
Knowing if you carry a mutation allows you to make a personalized breast care plan, which may include being screened at a younger age and more often. Breast screening with MRI is now recommended for BRCA1 and BRCA2 carriers. MRI in combination with mammography is better than mammography alone at finding breast cancer in women with these mutations [224].
Screening and prevention options for ovarian cancer
BRCA1 and BRCA2 carriers also have a higher risk of ovarian cancer. Women who know they have a mutation may consider screening and prevention options (such as oophorectomy) to reduce the risk of ovarian cancer. Learn more about prophylactic oophorectomy.
Benefits for family members
Getting genetic testing lets you share your test results with family members, who may benefit from them. Knowing genetic status allows family members the chance to join breast cancer research studies on new prevention methods.
Finding clinical trials for BRCA1/2 carriers
To search for clinical trials recruiting those with BRCA1/2 or other genetic mutations, visit http://breastcancertrials.org or the National Institutes of Health website at http://clinicaltrials.gov.
Support for BRCA1/2 carriers
Some support groups are tailored for people with BRCA1/2-related breast cancers. Our Support section offers a list of resources to help find a local or on-line support group. For example, the organization FORCE has on-line support for women affected by hereditary breast and ovarian cancer.
Updated 11/11/11
