Exploring racial disparities in BRCA testing for triple negative breast cancer patients: A real-world data analysis

Abstract Background and Objective: BRCA testing for patients (pts) with triple negative breast cancer (TNBC) is important because it has secondary prevention implications for patients and multigenerational implications allowing for earlier detection of BRCA gene carriers in the family and enabling primary prevention. And with the advent of PARP inhibitors it also has treatment implications. The NCCN guidelines recommended in January 2015 that BRCA testing be performed for all pts with TNBC diagnosed at age 60 or younger regardless of race, ethnicity or family history. To understand disparities in BRCA testing among TNBC pts we analyzed the proportion tested, explored barriers to testing, and made comparisons by race, ethnicity, and socioeconomic status (SES). Methods: Adult pts with TNBC diagnosed at or under age 60 between January 1, 2015 and December 31, 2020 were identified in the Syapse Learning Health Network, a real-world database with clinical and genomic data from community health systems. Study end was June 1, 2021, allowing for a minimum follow up of 5 months. Electronic health records were reviewed to calculate proportion tested and barriers to testing. SES was estimated using zip code level median household income from the 2010 census and stratified based on the national poverty level (low <150%, middle 150-299%, high 300%+). χ;2 statistics were used to assess differences between groups. Results: 577 pts with a median age at TNBC of 50 and median follow up of 18 months were included. 65.2% self-identified as white, 27.9% as Black or African American (AA), 1.4% Asian, 1.4% American Indian or Alaska Native, and 4.2% other. 8% identified as Hispanic/Latino. Due to relative size of racial/ethnic groups, the stratified analyses focused on comparisons between white and AA pts. Overall, 459 (79.5%) pts received a test, but with 83% of white pts receiving tests as compared to 72.7% of AA pts (p=0.009). 71.4% of pts with low SES received a test vs. 81.8% for middle and 79.4% with high SES (p=0.068). Among the 118 pts with no test, 48 (40.7%) did not have documentation of a test referral or evidence of testing offered in clinician notes. This differed by race with white pts less likely to have test offer documented vs. AA pts (53.1% vs. 72.7%, p=0.064). Among the 48 pts with no evidence of test offer, additional details were often not documented. However some clinician notes cited a perceived ineligibility due to lack of family history, transferring out or move to hospice, and pt refusal. Among the 70 (59.3%) pts who were offered a test but did not receive it, reasons included 37.1% choosing not to be tested, 11.4% due to early death, loss to follow up or transferring away, and 7.1% lacked adequate health insurance. These reasons varied by race, with 59.4% of AA pts choosing not to be tested vs. 20.6% of white pts (p=0.003) (Table 1). Conclusions: Real-world data provides insight into BRCA testing patterns in routine clinical practice where racial disparities are well documented and persistent. While the overall proportion of pts who received BRCA testing was high, AA pts experienced more barriers. Despite AA pts having greater evidence of a test offer vs. white pts, there was a significant gap in testing favoring white pts, with the most notable reason for lack of testing being pt choice. The clinical significance of BRCA testing in TNBC indicates a need to create targeted strategies to close gaps in education, confidence and access among patients and providers to improve testing levels. Table 1.BRCA testing barriers among patients who were offered a test but did not receive it (N=70)Total (n=70)White (n=34)Black or African American (n=32)Low SES (n=19)Middle SES (n=43)High SES (n=8)Lack of adequate health insurance, n (%)5 (7.1)3 (8.8)1 (3.1)3 (15.8)1 (2.3)1 (12.5)Patient chose not to be tested, n (%)26 (37.1)7 (20.6)19 (59.4)8 (42.1)14 (32.6)4 (50.0)Deceased before testing occurred, n (%)5 (7.1)3 (8.8)2 (6.3)1 (5.3)4 (9.3)0 (0)LTFU/Transferred, n (%)3 (4.3)2 (5.9)1 (3.1)1 (5.3)1 (2.3)1 (12.5)Other, n (%)7 (10.0)6 (17.6)1 (3.1)1 (5.3)6 (14.0)0 (0)Unknown, n (%)24 (34.3)13 (38.2)8 (25.0)5(26.3)17 (39.5)2 (25.0) Citation Format: Jeanna Wallenta Law, Hanadi BuAli, Sherri Costa, Michael P. Mullane, Mohamed Hendawi, Michael McPhee, Bryanne Collini, Mahder Teka, Francesca Coutinho, Ronda Broome, Frank M. Wolf, Liz Toland, Trista Weber, Anna Berry, Thomas D. Brown, Haythem Ali. Exploring racial disparities in BRCA testing for triple negative breast cancer patients: A real-world data analysis [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-14-17.