Risks
There's no medical risk associated with the BRCA gene test or any other genetic test that looks for a risk of breast and ovarian cancers. Having blood drawn for the test carries some minor risks. These may include bleeding, bruising and lightheadedness. Other effects of genetic testing include the emotional, financial, medical and social implications of your test results.
If you test positive for a harmful gene change, you may face:
- Feeling anxious, angry, or sad about your health and your family's health.
- Concerns over possible unfair treatment by insurers.
- Strained family relationships.
- Difficult decisions about the steps to take to prevent cancer.
- Coping with the worry that you'll eventually get cancer.
There also may be some emotional concerns if you test negative or if you receive results that aren't clear-cut. In these situations, there may be:
- "Survivor guilt" if family members have positive results and you don't.
- Uncertainty and concern that your result may not be a true negative result. This can happen if your results show you have a gene change that healthcare professionals aren't sure about.
Your genetic counselor or another professional trained in genetics can help you work through any of these feelings. That person can provide you and your family support throughout this process.
How you prepare
The first step in the BRCA gene testing process is to have genetic counseling. To do this, you meet with a genetic counselor or another healthcare professional trained in genetics. This person can help you understand whether testing is right for you and which genes should be tested. You also discuss the potential risks, limitations and benefits of genetic testing.
The accuracy of genetic testing depends partly on what the test is designed to find. Genetic tests look for the harmful gene changes included in the test. But different tests look for different gene changes. A genetics professional can help make sure the test ordered looks for the gene changes most likely to matter based on your personal and family history.
The genetic counselor or other genetics professional asks detailed questions about your family and medical history. The information helps assess your risk of having an inherited gene change that increases the risk of cancer.
To prepare for your meeting with the genetics professional:
- Gather information about your family's medical history, especially that of blood relatives.
- Document your personal medical history. This includes collecting records from specialists or results of previous genetic testing, if available.
- Write down questions to ask about genetic testing.
- Consider having a friend or family member come with you. That person can help ask questions or take notes.
It's up to you whether you choose to have genetic testing.
If you decide to have genetic testing, prepare yourself. Consider the emotional and social effects that learning your genetic status might have. Test results also may not provide you with clear-cut answers regarding your cancer risk. So prepare to face that possibility too.
At-home genetic test kits purchased online without talking with a healthcare professional may come with limitations. These kits may not look for all harmful BRCA1 or BRCA2 changes or for other genes that can increase the risk of breast and ovarian cancer. For example, one direct-to-consumer test checks for three harmful BRCA variants even though hundreds of BRCA variants can increase cancer risk. This means a negative result from an at-home test may not rule out an inherited cancer risk. If you are considering at-home testing, talk with a genetic counselor or another healthcare professional trained in genetics to make sure you get the right test and understand what the results mean.
What you can expect
The BRCA gene test is most often done as a blood test. A member of your healthcare team inserts a needle into a vein, usually in your arm. The needle draws out the blood sample. The sample goes to a lab for DNA testing.
Sometimes other sample types are collected for DNA testing, including saliva or a swab of cells from inside the cheek. If you are interested in a saliva or another DNA test, discuss this with your care team. A genetic counselor or other health professional trained in genetics can tell you the best sample type for your genetic testing.
Results
The results of a BRCA gene test may take a few weeks to come back. You meet with your genetic counselor or other health professional trained in genetics to find out your test results. You also discuss what the results mean and go over your options. Genetic testing is most useful when the results are reviewed along with your personal history, family history and goals for care.
Your test results may be positive, negative or uncertain.
Positive test result
A positive test result means that you have changes in a gene that are associated with a higher risk of cancer. But a positive result doesn't mean that you're certain to develop cancer.
After testing positive for a BRCA gene change or another gene change that could increase cancer risk, your healthcare team creates a care plan. The care plan depends on many factors. These may include the gene change found, your age, your medical history, past treatments and surgeries, and your personal preferences. After a positive BRCA test, next steps could include one or more of the following:
- Cancer screening that starts earlier or happens more often. For increased breast cancer risk, this may include mammograms and breast MRI. For men with harmful BRCA gene changes, recommendations may include mammograms for male breast cancer screening and prostate cancer screening. Some people with harmful BRCA gene changes and a family history of pancreatic cancer also may think about pancreatic cancer screening.
- Medicines. Some people may talk with their care teams about medicines as part of a plan to lower cancer risk. For breast cancer risk, options may include medicines such as tamoxifen or raloxifene. These medicines can lower breast cancer risk in women at higher risk because of a personal or family history. It's less clear how much they help prevent a first breast cancer in people with a strong inherited BRCA risk. For people with harmful BRCA1 or BRCA2 gene changes who already have had breast cancer, tamoxifen may help lower the chance of a new cancer in the other breast. To lower ovarian cancer risk in people with harmful BRCA1 or BRCA2 gene changes, oral contraceptives may help, but they can have possible harms. Talk with your care team about the benefits and risks before using medicine to lower cancer risk.
- Bilateral mastectomy surgery. To lower the risk of a future breast cancer, some people may consider surgery to remove both breasts. This is called bilateral risk-reducing mastectomy.
- Salpingo-oophorectomy surgery. There is no screening test proved to find ovarian cancer early enough to improve long-term survival. People with harmful BRCA1 or BRCA2 gene changes may choose surgery to remove the ovaries and fallopian tubes. This is called risk-reducing salpingo-oophorectomy. Some people also may talk with their care teams about whether to remove the uterus at the same time. This is called hysterectomy. The timing of this surgery and whether to have a hysterectomy depend on many factors. These include age, plans for pregnancy, menopause concerns and personal preferences.
- Reproductive planning. If you desire to have children, your care plan may include reproductive planning. If you have not gone through menopause and have harmful BRCA1 or BRCA2 gene changes, you may choose to have your fallopian tubes removed first and your ovaries removed later. Ovarian cancer often starts in the fallopian tubes. This approach is being studied. People who choose it usually are advised to have the ovaries removed later to lower ovarian cancer risk more fully.
- Genetic testing for blood relatives. If you have a harmful BRCA1 or BRCA2 gene change, your parents, siblings and children may have a chance of having the same gene change. Sharing this information may help family members and future generations decide whether to consider genetic counseling or testing. If your blood relative has a harmful BRCA1 or BRCA2 gene change, you may be offered testing for that same gene change. A genetic counselor or other health professional trained in genetics can help you understand what your relative's result may mean for you and your family and your future healthcare needs.
- Cancer treatment. If you already have cancer, genetic test results may help your care team choose cancer treatments or find clinical trials that may be right for you.
Negative or uncertain test result
A negative test result means that no gene changes were found. However, you could still have a higher risk of cancer.
A negative result is considered a "true negative" only if it finds that you don't carry the specific harmful gene change that runs in your family. This type of negative test result means you have the same cancer risk as the general population.
An uncertain test result might happen if your results show a gene change that healthcare professionals aren't sure about. This is called a variant of uncertain significance (VUS). A genetic counselor or other healthcare professional trained in genetics can help you understand this result.
Researchers continue working to discover new gene changes. The research helps health professionals understand how the gene changes might affect cancer risk. In time, many variants of uncertain significance are reclassified. Most are later found not to increase cancer risk. To be informed when this happens, stay in touch with the member of your care team who ordered your genetic test.
Genetic testing is an active area of research. If your gene test was done more than five years ago, your care team might recommend testing again with newer tests. If your family health history changes, such as if additional family members develop cancer, your team also might recommend more genetic testing.
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