What is BRCA testing?
BRCA1 and BRCA2 play a role in DNA repair and help keep breast, ovarian and other types of cells from growing uncontrollably. They’re referred to as tumor suppressor genes because when changes (mutations) in those genes develop, there’s an increased risk of breast, ovarian and other cancers. BRCA stands for BReast CAncer gene.
BRCA mutations are inherited; meaning, they’re passed down from your parents and run in families. To test for BRCA mutations, your healthcare provider takes a sample of your blood and analyzes it. This genetic test identifies any mutation in one of the BRCA genes.
Who should get BRCA testing?
BRCA gene mutations are rare. They only affect about 0.2% of the U.S. population. Most healthcare providers don’t recommend BRCA testing unless you have other specific risk factors.
Your healthcare provider may recommend BRCA testing if you have:
- A personal history of breast cancer, especially cancer diagnosed before age 50.
- A relative already diagnosed with a BRCA mutation.
- One or more family members who’ve had breast cancer, especially male breast cancer.
- Received a diagnosis of both breast and ovarian cancer.
- Ashkenazi Jewish ancestry.
- A personal or family history of multiple cancer diagnoses.
- A family history of an inherited cancer predisposition disorder, such as Cowden syndrome, Fanconi anemia, Li-Fraumeni syndrome or Peutz-Jeghers syndrome.
What can BRCA testing tell me?
Having a BRCA1 or BRCA2 gene mutation greatly increases your risk of breast cancer. People with a BRCA mutation may be up to six times more likely to get breast cancer by age 80 than the general population. Cancer might also develop at an earlier age and is more likely to affect both breasts.
BRCA mutations can also increase the risk of:
- Ovarian cancer and two related cancers: fallopian tube cancer and peritoneal (abdominal lining) cancer.
- Prostate cancer.
- Pancreatic cancer.
- Fanconi anemia (rare cancer that develops during childhood).
What happens before BRCA testing?
Before having BRCA testing, you’ll meet with a genetic counselor. Your counselor will explain how your inherited genes could affect your cancer risk. They’ll help you understand:
- What a positive or negative BRCA test result means.
- How your results affect your risk.
- What your results mean for your family members’ risk.
What happens during BRCA testing?
BRCA testing requires a single vial of blood. The procedure is the same as getting blood drawn for any blood testing or blood donation. Your healthcare provider inserts a thin needle into a vein in your arm to draw blood into the vial.
You may feel a prick or sting as the needle goes into or out of your vein. The procedure takes five minutes or less. If you have any bleeding, you can place a bandage over the spot.
What happens after BRCA testing?
Your healthcare provider will let you know when to expect results. You should schedule a follow-up appointment with a genetic counselor. This genetic specialist can help you understand the results and explain your options.
What are the benefits of BRCA testing?
Knowing whether you have a BRCA gene mutation helps you better understand your cancer risk. The test can also provide your family with information that affects their health. There are also more comprehensive genetic testing panels available with several genes analyzed in addition to BRCA1/BRCA2. Your genetic counselor can help guide you to which type of test is most appropriate in your case.
What are the risks of BRCA testing?
The test itself has very little risk. It’s a simple blood draw. In some cases, your healthcare provider might test a saliva sample.
Results and Follow-Up
When should I know the results of the BRCA testing?
In most cases, you should have results in a few weeks. Some labs can speed results for people who’ve already been diagnosed with cancer and need results to help make treatment decisions. Ask your healthcare provider when you can expect your results.
What does it mean if the results are positive?
Testing positive for a BRCA mutation significantly increases your risk of cancer. But it doesn’t mean you’ll definitely get cancer. Knowing that you have a BRCA gene mutation enables you to take positive steps to prevent cancer. It also helps your family members to better understand their own risks.
Talk to your healthcare provider and genetic counselor about whether your relatives should be tested. Your counselor and healthcare provider can also explain preventive measures you might want to take. Possible steps include:
- More frequent cancer screenings (such as mammograms).
- Additional screening techniques (such as breast MRI).
- Limited use of birth control pills, which may reduce your risk of ovarian cancer but can raise the risk of breast cancer in some people.
- Use of cancer-preventing medications, such as tamoxifen.
- Preventive surgery, such as a prophylactic (preventive) mastectomy to remove healthy breast tissue before cancer can develop, and prophylactic removal of ovaries and fallopian tubes to reduce the risk of developing ovarian cancer.
What does it mean if the results are negative?
A negative result means you don’t have a BRCA mutation. It also means your children won’t inherit a BRCA mutation from you.
A negative BRCA test doesn’t guarantee you won’t get cancer. It means your risk is likely the same as the general population. Knowing your results can help your care team plan your treatment if you ever receive a cancer diagnosis.
If your test is negative, but you have one or more family members diagnosed with breast cancer before age 50, the implications are less clear. It may mean your family has a different gene mutation that increases cancer risk. Your genetic counselor can help you understand these results and decide if you need any further testing.
What does it mean if the results are uncertain?
It’s possible to get inconclusive results, which may require further testing. Your test may show that you have a change in the BRCA1 or BRCA2 gene, but not a mutation known to be associated with increased breast cancer risk.
This result is a variant of unknown significance (VUS). Your genetic counselor can explain these results and help you decide if you — or other family members — should have further genetic testing.
What questions should I ask my healthcare team?
- Which other members of my family should also get BRCA testing?
- If my test is positive, does that mean my children also have the gene mutation?
- How does my test result affect breast cancer screening, as well as screening for other types of cancer?
- If my test is positive, are there any steps I should consider to reduce my risk of developing certain types of cancer?
- Can the type of testing I had also find other gene mutations?
A note from Cleveland Clinic
BRCA testing looks for abnormal changes in the BRCA1 and BRCA2 genes. A positive test result means you have a higher-than-average risk of developing breast, ovarian and other cancers. Knowing you have a BRCA gene mutation also means you can take steps to lower your risk and help prevent cancer.
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