Breast cancer is the most common cancer diagnosed in women younger than 40 years old in the US. Mutations in the BRCA1 and BRCA2 genes, which are involved in DNA repair, can significantly increase an individual’s risk for breast and ovarian cancer, as well as recurrent cancers or later cancer in the opposite breast.
Knowing the status of the patient’s BRCA1/2 mutations can drastically impact subsequent treatment options. Thus, doctors often recommend that young women diagnosed with breast cancer undergo genetic testing to determine the mutation status for both BRCA genes.
But do these genetic results influence subsequent treatment choices for the young patients? To answer this question, researchers analyzed data from 897 women diagnosed with breast cancer at or younger than 40 years old.
Led by Ann H. Patridge of the Dana-Farber Institute in Boston, the research team found that within one year after diagnosis, 87 percent of the women had undergone BRCA testing. This testing frequency increased over time. Of women diagnosed, nearly 77% underwent testing in 2006, 96.6% were tested in 2012, and 95.3% were tested in 2013.
Among those who were tested, 7.6% were positive for BRCA1 mutations, and 4.5% had BRCA2 mutations. Meanwhile, 4.6% of patients had inconclusive results with variants of unknown significance.
These test results had meaningful impacts on how women chose to proceed with their treatment options. The data showed that 86% of patients who tested positive for mutations in either BRCA genes opted for bilateral mastectomies. The carriers were also more likely to undergo preventative ovary removal. Of the non-carriers (51.2%), the data showed that this group of women had a surprisingly high rate of bilateral mastectomy.
Since becoming commercially available in 1996, BRCA testing has gained widespread notoriety in the
The authors also noted that most of the women in the study were insured, educated, and had access to a selection of testing and treatment services. This, the authors say, could have also influenced the high frequency of BRCA testing in the study group.
Overall, the increased rate of BRCA1/2 mutation testing in young women with breast cancer is a positive trend. One important corollary that will hopefully be addressed next is the counseling and support aspect of mutation testing. Genetic counseling is a crucial component of genetic testing, and it would be curious to know if and how this support system has changed to accommodate the increase.
Additional source: US News