Your genes are like an encyclopedia. They contain valuable information about you—for example, your eye color, height, or skin tone. They can also determine your risk for certain diseases, including breast cancer. Genetic testing may help some women take action against this potential health concern. Is it right for you?
Some women are born with a genetic mutation, or change, that makes them especially prone to breast cancer. They specifically have a defect in one of their breast cancer susceptibility genes, or BRCA1 and BRCA2 genes. The mutation increases a woman's risk not only for breast cancer, but also for cancers of the ovaries, fallopian tubes, and the inner lining of the abdominal wall (peritoneum).
Women who inherit a mutation in their BRCA1 are 55% to 60% more likely to develop breast cancer. Women with a BRCA2 mutation have a 45% increased risk. These women usually have a family history of breast or ovarian cancer. In particular, they often have more than 1 family member diagnosed at an early age with either disease. They may also have a family member who has had both.
Even if you have a family history of breast cancer, you still may not have the mutation. In fact, few women do. That's why the U.S. Preventive Services Task Force—an independent panel of health experts—recently issued guidelines on genetic testing for BRCA1 and BRCA2. Only women with a family history that points to such a mutation should consider genetic testing.
If you have a family history of breast cancer, talk with your doctor about screening for the BRCA1 and BRCA2 mutations. Ask if you should consider genetic testing. It often requires only a blood sample, but not all insurance companies cover it. Based on the screening, your doctor may suggest you speak with a genetic counselor.
Genetic counselors can help you make an informed decision about genetic testing. These specialists can tell you more about the benefits and risks. They can discuss your inheritance patterns and explain your testing options.
A genetic counselor can also help you and other family members cope with the results, which may not always be clear-cut. In some cases, a woman may receive an ambiguous answer. That can happen if the test finds a different mutation that hasn't been linked to cancer.
If you receive a negative result, it may ease your anxiety. But it doesn't mean you won't get breast cancer. On the flip side, a positive result doesn't necessarily mean you will develop it. Instead, it gives you the opportunity to reduce your risk.
Some women with the mutation may decide on more frequent breast cancer screenings. A few may choose to take cancer-preventing medication, such as tamoxifen. Others may consider surgery to remove one or both breasts. Although potentially helpful, these strategies can have side effects and complications, too.
What is your risk for breast cancer? Find out with this risk assessment tool. Use the results to talk with your doctor about how you can prevent the disease
American Cancer Society
National Cancer Institute