Genetic Testing Appropriate for Some Women with Triple-Negative Breast Cancer
A study conducted in Greece found elevated rates of BRCA1 gene mutations in women with triple-negative breast cancer, particularly those who had been diagnosed with cancer at a young age. These results were published in Breast Cancer Research and Treatment.
Inherited mutations in two genes—BRCA1 and BRCA2—have been found to greatly increase the lifetime risk of developing breast and ovarian cancer. Mutations in these genes can be passed down through either the mother’s or the father’s side of the family.
Genetic testing for BRCA mutations may be recommended for people who have an increased likelihood of a mutation based on their own or their family’s cancer history. If a mutation is identified, women can consider more intensive cancer screening, use of medications to reduce cancer risk, or preventive surgery to remove the breasts and/or ovaries before cancer develops.
Women with a BRCA1 mutation have a high likelihood of developing triple-negative breast cancer (breast cancer that is hormone receptor-negative and HER2-negative): up to three-quarters of the breast cancers diagnosed in women with a BRCA1 mutation are triple-negative.
There’s been less information about how common BRCA1 mutations are in women with triple-negative breast cancer, but studies conducted thus far suggest that rates are elevated.
To further explore the frequency of BRCA1 mutations, researchers in Greece conducted a study among 403 women with triple-negative breast cancer.
- Overall, 16% of the women were found to have a BRCA1 mutation.
- BRCA1 mutations were more common in women who were diagnosed with triple-negative breast cancer at a young age: mutations were found in 36% of women diagnosed under the age of 40, and 27% of women diagnosed under the age of 50.
- BRCA1 mutations were also more common in women with a family history of breast or ovarian cancer. Close to one-quarter of the mutations, however, were found in women with no reported family history of breast or ovarian cancer.
These results provide additional evidence that women with triple-negative breast cancer—particularly those diagnosed at a young age—have elevated rates of BRCA1 mutations and may be candidates for genetic testing.
In the United States, the National Comprehensive Cancer Network (NCCN) recommends genetic risk assessment, counseling, and management for women diagnosed with triple-negative breast cancer at age 60 or younger. Women with other personal or familial characteristics suggestive of a BRCA1 or BRCA2 mutation may also be candidates for testing. Decisions about genetic testing are complex, and genetic counseling provides individualized information about the need for testing and the implications of testing.
 Fostira F, Tsitlaidou M, Papadimitriou C et al. Prevalence of BRCA1 mutations among 403 women with triple-negative breast cancer: implications for genetic screening selection criteria: a Hellenic Cooperative Oncology Group Study. Breast Cancer Research and Treatment. 2012;134:353-3.
 National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®). Genetic/familial high-risk assessment: breast and ovarian. V.1.2012. Accessed August 21, 2012.
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