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Real-World Data Points to Racial Disparity in BRCA1/2 Testing Among TNBC Patients

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NEW YORK – An evaluation of real-world BRCA1/2 testing patterns among triple-negative breast cancer patients has shown that African American women within four community health systems in Syapse's Learning Health Network are facing more barriers in accessing testing.

At the San Antonio Breast Cancer Symposium on Thursday, researchers from real-world evidence company Syapse, and four health systems — Henry Ford Health system in Michigan, Advocate Aurora Health and Ascension both in Wisconsin, and AdventHealth in Florida — described efforts to track BRCA1/2 testing rates among patients diagnosed with TNBC at age 60 or younger between Jan. 1, 2015, and Dec. 31, 2020. In the study, which ended on June 1 of this year to allow for a minimum five-month follow-up, researchers identified 577 TNBC patients, of whom 375 self-identified as white and 162 as Black.

BRCA1/2 testing is important for TNBC patients because knowledge of an inherited mutation can impact their relatives' cancer risk management. During the study period, the National Comprehensive Cancer Network recommended that all TNBC patients diagnosed at age 60 and younger should be assessed for germline mutations in these two genes, regardless of family history, race, or ethnicity.

Overall, 459 patients or nearly 80 percent of all TNBC patients identified in the study received BRCA1/2 testing, but there was a racial disparity in testing rates, with 83 percent of white patients receiving tests compared to 73 percent of Black patients.

Then, researchers looked at the 118 patients who did not receive testing to try to glean from real-world data some additional details, for example, if their doctors documented in clinic notes whether testing was offered and why patients didn't receive testing. In this group, 48 patients didn't have any documentation in clinic notes that their doctors offered them BRCA1/2 testing, while 70 patients were offered testing according to physicians' notes but still didn't receive it.

Black patients were more likely to have documentation in clinic notes of testing being offered (73 percent) compared to white patients (53 percent). Although additional details around why a doctor may have decided not to offer testing weren't often available, some physicians' notes "cited a perceived ineligibility" for patients lacking family history of cancer.

Since the analysis included TNBC patients between ages 19 and 60, all the patients in this analysis met NCCN guidelines during the study period for BRCA1/2 testing. Many studies now have shown that family history is often insufficient to identify patients who harbor mutations in cancer risk genes, such as BRCA1/2. As of August this year, NCCN recommends BRCA1/2 testing for all TNBC patients, regardless of age and family history.

Thomas Brown, Syapse's chief medical officer, said in an interview that from the present analysis it's not clear whether this misperception in some documented cases about not qualifying for testing because of insufficient family cancer history came from the doctor or the patient, but either way it's an inaccurate understanding of the latest guidelines. "The evidence-based recommendations that constitute the NCCN guidelines are clear that if a patient has triple-negative breast cancer they should be tested for BRCA1/2 gene alterations," Brown said.

Another reason clinicians noted for TNBC patients not getting tests was that they were going to hospice because they had gotten too sick. Still others noted that patients refused testing.

Specifically, of the 70 patients who were offered testing but didn't receive it, researchers' real-world data analysis revealed that 37 percent of patients were documented as "unable to receive" or having "declined testing," while other recorded reasons for lack of testing included early patient death in 7 percent, loss to follow-up or transfer in 4 percent, and inadequate insurance coverage in 7 percent of cases.

Among those unable to receive testing or who declined it, there were more Black TNBC patients (59 percent) compared to white patients (21 percent), suggesting Black patients have more barriers when accessing tests.

Brown, who was also an investigator on the real-world evidence analysis reported at SABCS, noted that the research team considered carefully how to describe these patients who couldn't get testing. While the poster describes the 37 percent of patients as "unable to receive or having declined testing," the abstract submitted to SABCS describes that subset as "choosing not to be tested."

"The word 'chose' for all of those within that 37 percent is inaccurate," in Brown's view, "because in some cases it appeared that patients may have wished to be tested, but due to their life circumstances, they were unable to be tested."

Researchers led by Jeanna Law, a cancer epidemiologist at Syapse, and Haythem Ali, a medical oncologist at the Henry Ford Health System, did not look at the specific reasons why patients were unable to get testing or why more Black patients declined testing altogether. But this could be evaluated in future real-world data studies, Brown said.

Studies on patients declining clinical trial participation, for example, have found cost and insurance to be big barriers. Within the real-world data Syapse collected from four community healthcare systems, the researchers were also able to look at socio-economic status and found that TNBC patients with low socio-economic status were less likely to get BRCA1/2 testing compared to those with middle or high socio-economic status, though this analysis wasn't statistically significant.

Practical concerns, such as lack of transportation to appointments or the inability to find childcare and take time off from work, can also present hurdles for patients. Given the history of racism and unethical research in the US, trust in the medical establishment may also be a factor in some communities.

"All of us who are engaged in this type of work, especially in the US, recognize we have to get beyond just identifying healthcare disparities and address them," Brown said. From this research, Syapse hopes that healthcare organizations in its network will see that while the overall rates of BRCA1/2 testing may be relatively high in TNBC patients, there's still evidence of disparities based independently on race and income.

"The next step is to better understand the reasons why patients are not being tested and addressing those reasons, whether it's a matter of trust or a matter of more practical issues like transportation," Brown said. Based on Syapse's real-world evidence research in other areas of genetic testing, he highlighted that some healthcare organizations have implemented process improvements, such as a centralized system for ordering genetic testing, reflex testing for certain biomarkers and indications, and molecular tumor boards to help doctors make appropriate decisions based on test results.

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