If you’re thinking about learning whether you have mutations for the BRCA1 or 2 genes, it’s important to consider both the benefits and drawbacks of learning this information.
Here are the advantages of seeking genetic testing:
If you have a family member with a confirmed BRCA mutation, and your test result is negative, your genetic counselor can tell you with greater certainty that you have the same relatively low risk of developing breast or ovarian cancer as people in the general population. Routine screening for breast cancer (self-exams, mammograms, doctor visits) will still be important for you, just as it is for all women. For ovarian cancer there are currently no widely accepted screening guidelines for women at average risk of developing the disease. Men with a negative test result know that they have the same extremely low risk of getting male breast cancer as men in the general population, and the same relatively low risk of prostate cancer.
If your test result is positive, there are steps you can take to lower your risk of breast and/or ovarian cancer, or try to detect these cancers early if they should ever develop:
- Talk to your doctor about the possibility of taking a medication such as tamoxifen, which could reduce your risk of developing breast cancer, or oral contraceptives, which could reduce your risk of ovarian cancer. While data is not clear on the safety of oral contraceptives in people at high risk for breast cancer, some doctors do recommend them for carriers of BRCA1 and BRCA2 mutations. This recommendation depends on factors including which mutation you carry and how much breast or ovarian cancer is in your family. Weigh the pros and cons of oral contraceptives with your doctor. You also may want to participate in a clinical trial on breast and/or ovarian cancer prevention to see whether other medications may be effective.
- You might take advantage of more frequent clinical exams and breast screenings — every 6 months instead of once per year — and ask for digital mammography (versus film screen mammography) and/or MRI (magnetic resonance imaging) in addition to mammography. You also may wish to have regular pelvic exams and ultrasounds, and possibly a blood test called CA-125, in an attempt to detect any early signs of ovarian cancer.
- You may consider preventive (prophylactic) surgical removal of your breasts, ovaries, or both before cancer has an opportunity to form.
- If you do develop cancer, you and your doctor will be able to make treatment decisions that take your genetic information into account.
- You can contribute to research that could eventually help to prevent or cure breast or ovarian cancer if you had genetic testing as part of a research program or if you participate in other clinical studies.
- Knowing that you carry a BRCA mutation may prompt you and your family members to make lifestyle and family planning changes or other decisions that could help lower cancer risk.
Men who test positive for BRCA mutations are considered to be at higher-than-average risk for prostate cancer. They can talk with their doctors about beginning screenings, including an annual digital rectal examination and PSA (prostate-specific antigen) blood test between ages 40 and 50. Their risk of male breast cancer is still relatively low, but higher than it is for men who do not have the mutation. Men should be sure to report any unusual breast changes or lumps to their doctors immediately.
Genetic testing also has limitations and possible drawbacks, including the following:
- It's not yet clear exactly what you should or shouldn't do once you get your genetic test results. We still don't know the most effective ways to prevent breast or ovarian cancer, although taking certain medications, such as tamoxifen for breast cancer and, in some cases, oral contraceptives for ovarian cancer, could lower your risk of developing these diseases.
- Removing the breasts and ovaries to lower cancer risk (called prophylactic surgery) does not get rid of every breast- and ovary-related cell. So even though surgery lowers your risk dramatically, it still does not entirely eliminate the risk. Even after such surgery, a woman with an abnormal breast cancer gene must be monitored regularly. These diseases may show up in nearby tissues and organs.
- Normal test results don't guarantee healthy genes. In some families, many women have had breast cancer, yet they all test normal for the known breast cancer mutations. These families may have an inherited form of breast cancer caused by an abnormality or other gene that simply hasn't been identified yet. Also, if a woman tests negative for the mutations but the presence of a mutation has not been confirmed in a family member with cancer, she still is considered high-risk. In these situations, women need to be followed closely by their doctors. For more information on genetic testing, counseling, and support, visit the FORCE (Facing Our Risk of Cancer Empowered) Web site.
- Close monitoring with regular exams and screening does not always succeed in detecting breast and/or ovarian cancer early. Some women end up being diagnosed with later-stage disease despite the best surveillance techniques.
- For some women, an abnormal test result can trigger anxiety, depression, or anger. Even though the result doesn't mean that a woman will definitely get breast cancer, many women with an abnormal gene assume they will. If you think knowing the information may be too hard for you emotionally, you might consider not having genetic testing until more is known about how to prevent and treat the disease.
- If you learn that you've passed on an abnormal gene to your children, you may feel guilty and worried. (Yet such knowledge may also prepare you for helping your children cope with their genetic information.)
- You could face discrimination — in getting insurance coverage or employment — based on your genetic information. So far, however, discrimination related to genetic information has not proven to be a major problem. In 2008, the Genetic Information Nondiscrimination Act (GINA) was signed into law. It protects Americans against discrimination based on their genetic information when it comes to health insurance and employment.
- Genetic testing may not answer all your questions. In families with an abnormal breast cancer gene, other factors that are not yet understood may contribute to high risk.
The reality is that there have been very few documented cases of discrimination. That doesn't mean there isn't a potential of this happening, but the fears of discrimination have been greatly overemphasized. Cancer genetics specialists are usually well informed about state and federal laws on genetic discrimination and can help provide balanced and up-to-date information on this issue.