For breast cancer survivors who carry mutations in BRCA genes, preventive surgery can substantially reduce the risk of future breast and ovarian cancer. However, it appears that black women are far less likely to receive these widely recommended procedures than white or Hispanic women, according to a population-based study of breast cancer survivors in Florida.
“People only benefit from genetic testing for cancer risk if they act on the information the test reveals and receive appropriate follow-up care,” said lead study author Tuya Pal, MD, a Clinical Geneticist at the H. Lee Moffitt Cancer Center & Research Institute, Inc. in Tampa, Fla. “Our data showing lower uptake of risk-reducing surgery among minority BRCA carriers may prompt clinicians to provide more intensive, targeted follow-up efforts, especially for black women.”
Risk Management for BRCA Carriers
Once a woman who carries a BRCA mutation is diagnosed with breast cancer she faces up to a 50 percent lifetime risk of second breast cancer and up to a 44 percent risk of ovarian cancer. Preventive bilateral mastectomy greatly reduces the risk of a second breast cancer.
Similarly, surgical removal of ovaries and fallopian tubes (oophorectomy) cuts the risk of ovarian cancer by 90 percent. As there are no reliable screening options for early detection of ovarian cancer, preventive oophorectomy is a critical strategy to lower deaths from ovarian cancer in this population.
The researchers recruited non-Hispanic white (NHW), black, and Hispanic women diagnosed with an invasive breast cancer at or before the age of 50 through the Florida State Cancer Registry. According to the authors, this is the first study to explore follow-up care among BRCA carriers across an entire population treated in diverse settings, including a significant number of minority women. Prior studies were limited to a single academic center or health system.
Among the 1,621 participants, 917 reported BRCA testing following their breast cancer diagnosis, and 92 of those tested positive for the mutations.
The researchers identified genetic testing rates varied by racial group: 65 percent NHWs and 62 percent Hispanic women received testing, compared to only 36 percent of black women. The lower rates of clinical genetic testing for BRCA mutations in black women is unfortunate, as they may be missing an opportunity to take advantage of preventive interventions after breast cancer.
Among the 92 women who tested positive for BRCA mutations, the researchers also found significant differences in receipt of mastectomy and oophorectomy between the three racial groups. Black women had the lowest rates of both bilateral mastectomy (68%) and oophorectomy (32%). Compared to NHW women, Hispanic women had lower rates of mastectomy (85% vs. 94%), but higher rates of oophorectomy (85% vs. 71%). The differences between blacks and the other two groups remained significant after controlling for age at enrollment, time since diagnosis, income, family history of breast cancer and ovarian cancer and insurance status.
The authors acknowledged that the study has some limitations, which include:
- Small numbers of women with BRCA mutations in each racial/ethnic group (51 NHW, 28 black, and 12 Hispanic).
- The fact that four black women enrolled in this study were still in active treatment may contribute to lower rates of oophorectomy seen in this group.
- Given that breast cancer is a devastating diagnosis to women, it is possible that women may choose to pursue breast cancer treatment prior to addressing ovarian cancer risk management. Thus it is important to conduct follow-up studies among these women to determine their cancer risk management choices over time.
“I hope that our findings will raise awareness of disparities pertaining to inherited cancer predisposition that exist across the cancer care continuum. It is now imperative to understand why these disparities exist, so we can develop interventions to address them to ensure that women with inherited disease make informed decisions about their cancer risk management,” said Pal.
This study included women who were diagnosed with breast cancer between 2009 and 2012. Additional studies should be conducted to assess patients diagnosed more recently, to reflect recent changes that have impacted the U.S. health care systems. Most importantly, these include expiration of the BRCA gene patent in conjunction with tremendous technologic advances in DNA sequencing technologies, which have led to the lower costs of testing which is expected to make the test accessible to more people.