When actress Angelina Jolie tested positive for a BRCA1 gene mutation and she announced that she would undergo a proactive double mastectomy, she raised the awareness of the use of genetic testing in breast cancer prevention among women. While DNA testing potentially can be life saving, it’s important to understand who is a good candidate for the test and how results can help women make informed decisions about their health care.
What Are BRCA Genes?
BRCA1 and BRCA2 are genes that produce proteins that help repair damaged DNA and ensure the stability of the cell’s genetic material.
“The BRCA gene is something that’s in all of us, it’s part of our normal biology,” said Dr. John Anagnost, medical oncologist with Cape Fear Cancer Specialists - NHRMC Physician Group. “The gene works to keep cells from becoming abnormal. They prevent cells from multiplying out of control and thus prevent tumors before they begin.”
In a small percentage of the population, women inherit a harmful mutation of the BRCA1 or BRCA2 gene, which significantly increases their lifetime risk of developing breast or ovarian cancer.
“If you have a BRCA mutation, DNA repair doesn’t occur and you can have problems, in this particular case, breast or ovarian cancer,” said Dr. Anagnost.
Cancer Risk and Genetic Testing: Who Should Get Tested
Because the BRCA mutation is inherited, family history is an important indicator of who should consider testing.
“If a woman has a significant family history of breast or ovarian cancer, or has had a close relative who developed breast or ovarian cancer under the age of 50, she may benefit from doing genetic testing,” said Dr. Anagnost. “If we find one person with the gene mutation, we should look at the rest of the family.”
The United States Preventive Services Task Force recommends that women with an increased risk of having a BRCA mutation be referred to a genetics professional to discuss testing. In general, those without a significant family history should not be tested.
How Genetic Testing is Performed
DNA tests can be done from a blood or saliva sample.
“The test can be done with a simple blood test, but we can also perform what’s known as a ‘swish test,’ where the patient swishes and spits a sample into a container; there are enough cells in that material to examine,” said Dr. Anagnost. The sample is then sent to a laboratory for analysis and takes about two weeks for the test results to come back.
Options for Treatment
While genes are just one risk factor for breast and ovarian cancer, knowing genetic status can help women make important decisions. Options can include surgery, use of the antiestrogen medicine tamoxifen, and/or close monitoring.
“With the genetic information, the patient can talk with the genetic counselor and her physician about risks and decide what is best for her,” said Dr.Anagnost.
Genetic testing for disease is a complex issue, so it is recommended that women who are considering genetic testing for breast cancer receive counseling from a healthcare provider who can fully explain the benefits and risks of DNA testing and answer any questions they may have.
If you think you are at increased risk of developing cancer due to family history, talk with your primary care physician to find out if you may be a candidate for genetic testing.
Dr. Anagnost is a member of NHRMC Physician Group. For a free directory of NHRMC Physician Group providers, call 910.342.3400 or visit www.nhrmcphysiciangroup.org for a full list of NHRMC physicians.