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Breast Cancer (BRCA) Gene Test

How It Is Done

The health professional drawing blood will:

  • Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
  • Clean the needle site with alcohol.
  • Put the needle into the vein. More than one needle stick may be needed.
  • Attach a tube to the needle to fill it with blood.
  • Remove the band from your arm when enough blood is collected.
  • Apply a gauze pad or cotton ball over the needle site as the needle is removed.
  • Apply pressure to the site and then a bandage.

How It Feels

The blood sample is taken from a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight. You may feel nothing at all from the needle, or you may feel a quick sting or pinch.

It is common to worry before a BRCA test and while waiting for its results.

Risks

There is very little chance of a problem from having a blood sample taken from a vein.

  • You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for several minutes.
  • In rare cases, the vein may become swollen after the blood sample is taken. To treat this, you can use a warm compress several times a day.
  • Ongoing bleeding can be a problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can make bleeding more likely. If you have bleeding or clotting problems, or if you take blood-thinning medicine, tell your doctor before your blood sample is taken.

Some women may be worried about the test results and how it will affect their life insurance, disability insurance, or long-term care insurance.

Results

A breast cancer (BRCA) gene test is a blood test to check your chance of developing breast cancer and ovarian cancer. Test results may take several weeks.

Normal (called negative)

No changes were found in the BRCA1 or BRCA2 genes.

A negative result and your overall family risk must be considered together.

  • If a family member has a known BRCA change, other family members may want to be tested.
  • If your family member with breast or ovarian cancer tests negative for BRCA changes, you probably don't carry those changes, either. In this case, you have the same chance of cancer as that of the general public, based on your age and personal and family history.

Only about 5% to 10% of breast and ovarian cancers are linked to the BRCA1 or BRCA2 gene change. If you have a strong family history of breast or ovarian cancer, you may still have a higher chance of developing breast cancer even if you have a negative BRCA result. Other gene changes are possible that make cancer more likely.

Abnormal (called positive)

WebMD Medical Reference from Healthwise

Last Updated: June 28, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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