Genetic testing for BRCA1/2 mutations is recommended for all women with ovarian cancer, given the important implications for treatment and prognosis, according to the Caitlin E. Taylor, MD, lead author of a paper presented at the recent virtual Annual Meeting of ASCO. “Despite this recommendation, however, studies show that only a small percentage of patients with ovarian cancer undergo genetic testing,” Dr. Taylor says, adding that BRCA1/2 mutation status provides important information, not only regarding prognosis in ovarian cancer, but also in formulating a treatment plan. “Given the large Black patient population at our center, we specifically wanted to evaluate the association between race and genetic testing, since there is limited existing data on this issue.”
Overall Genetic Testing Rates Were Low
The study team aimed to identify factors associated with lower rates of genetic testing, using data from Winship Cancer Institute at Emory University in Atlanta. A retrospective chart review was performed, evaluating rates of referral and uptake for genetic testing, and percentages of BRCA mutation carriers among patients with ovarian cancer diagnosed and treated between 2008 and 2018. Associations between age, race, histology, family history, performance status, provider characteristics, and genetics referral and testing were evaluated using logistic regression models.
Of the 171 patients who met inclusion criteria, the majority were age 55 or older (62%) with high-grade serous carcinoma (60.8%). Patients were predominantly Caucasian (59.4%), followed by Black (29.1%), Asian (10.3%), and Hispanic (1.2%). Overall, genetic testing rates were low, according to the researchers, with 44.7% of patients referred for genetic counseling and 39.8% receiving testing. Among patients who did receive genetic testing, the percentage of deleterious BRCA1/2 mutations identified was 11% and 8.8%, respectively. Variables correlating with higher likelihood of genetics discussion, referral, and testing included serous histology (50% vs 23.9% non-serous), Caucasian or Asian race (87.5% Asian, 58.8% Caucasian vs 42.2% Black), and seeing a medical oncologist (67.5% vs 44.7% seeing a gynecologic oncologist alone).
Black Patients Found to Have Higher BRCA Mutation Rates
Notably, while fewer Black women were referred for genetic testing (25.9% vs 74.1% Caucasian), those that did undergo genetic testing were found to have higher rates of BRCA1/2 mutations when compared to Caucasian patients (22.2% vs 8.2% BRCA1; 11.1% vs 6.0% BRCA2). The study team also observed that patients with a family history of ovarian cancer were more likely to undergo genetic testing than those with a family history (69.2% vs 37.9%), and patients with a family history of breast cancer were more likely be referred for testing (57.1% vs 39.6%), suggesting that family history impacted referral patterns. “Our data showed a higher prevalence of mutation burden among Black patients, as well as lower rates of referrals to genetics and genetic testing among this same patient population,” says Dr. Taylor. “This really underscores the need to improve access to testing by addressing potential barriers and streamlining the genetic testing process as a whole to provide every patient with the best possible care.”
Dr. Taylor and colleagues stress that further research is needed to design interventions that may help improve adherence to this important recommendation in the future. “There are clearly multiple barriers to genetic testing that still exist,” she says. “Research on specific interventions to improve rates of genetic testing will be important in the future, particularly as we are likely to see more treatment options become available specifically for BRCA1/2-mutated malignancies.”
Testing for Mutations in BRCA1 and BRCA2 Among Ovarian Cancer Patents at a Diverse Academic Medical Center