More Young Women Using BRCA Test Results to Choose Treatment
More and more young women diagnosed with breast cancer are being tested for genetic mutations that mean a higher risk of developing a second breast cancer, a recent study in JAMA Oncology found. About 30 percent of those women make treatment decisions based on their genetic test results.
Women with a particular mutation in a BRCA gene have a higher risk of getting breast and ovarian cancer in their lifetime. The BRCA1 and 2 mutations are especially tied to breast cancer in young women. Guidelines from the National Comprehensive Cancer Network (NCCN) recommend women diagnosed at age 50 or younger get genetic counseling and possible testing for BRCA and other gene mutations.
Knowing whether they have a BRCA gene mutation may affect some women’s decisions about which breast cancer treatments to choose. For example, women with a BRCA mutation may choose to have surgery to remove both breasts, even when the tumor is only in one breast, to lower their chance of developing a new cancer.
The study researchers wanted to find out how often young women chose to have genetic testing. They also wanted to learn how genetic risk or concern about genetic risk affected women’s treatment decisions.
The researchers used data from an ongoing study of women diagnosed with breast cancer at age 40 or younger. The study was conducted in Massachusetts, Colorado and Minnesota. The period looked at for this analysis began in 2006 and continued through 2013.
Participants were asked if they had BRCA testing by 1 year after they were diagnosed. They were also asked if knowing about genetic risk, or being concerned about it, had affected their choice of treatments.
Of 897 women in the study, 780 (87 percent) had genetic testing by 1 year after diagnosis, and 12 percent of those women tested had a BRCA mutation.
The number of women who chose to be tested grew over the years of this study. In 2006, 76.9 percent of participants had testing. By 2013, 95.3 percent did.
For 248 women, concern about genetic risk affected their choice to get certain treatments.
- Many in this group decided to have surgery to remove both breasts.
- 86.4 percent of those with a genetic mutation
- 51.2 percent of women who did not have a mutation
- Fewer women chose to have their ovaries removed, to further lower their risk of getting a new breast cancer or ovarian cancer, which is also tied to the BRCA gene.
- 53 percent of those with a genetic mutation
- 2.5 percent of those without a mutation
If they had a gene mutation, the women were more likely to choose to remove their ovaries than if they did not have a mutation.
About half of the 117 women who were not tested said they or their doctor thought it was unlikely they had a genetic mutation. However, 36.8 percent of this 117 said they were thinking of being tested in the future.
The researchers noted that certain factors might have affected the results. Most participants were treated in cancer centers where genetic counseling and testing were likely available. Many of the women were college educated and nearly all had health insurance. Results might differ in areas served only by community medical centers and for women who cannot afford testing.
During much of the study period, only one lab was doing BRCA testing and only one BRCA test type was available. Today, genetic tests measure a wider range of genes that could raise breast cancer risk. The researchers said future studies should look at the use and effects of other tests.
What This Means for You
If you were diagnosed with breast cancer before age 50, NCCN guidelines recommend that you have genetic testing.
Knowing if you have a gene mutation can help you decide on treatment and help you have conversations about lowering your risk of a future, new breast cancer diagnosis. If you have a BRCA mutation, you may choose more surgery, such as a single or double mastectomy, or having your ovaries removed to lower the risk of getting a new breast or ovarian cancer. Testing positive for a BRCA mutation may also qualify you for certain clinical trials.
Your genetic results also may help your children, sisters, brothers and other family members understand their cancer risk.
Talk with your doctor or a genetic counselor about genetic testing. A genetic counselor can help you get tested and will explain the results so you can make choices that are right for you.
Rosenberg, SM, Ruddy, KJ, Tamimi, RM, et al. BRCA1 and BRCA2 Mutation Testing in Young Women with Breast Cancer. JAMA Oncology 2016; doi:10:1001/jamaoncol.2015.5941
This article was supported by the Grant or Cooperative Agreement Number 1 U58 DP005403, funded by the Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention or the Department of Health and Human Services.