Does race play a role in genetic screening for hereditary cancer syndromes?
1578 Background: Molecular analysis of cancer predisposition genes may influence cancer screening, prevention strategies and options for targeted therapy. We sought to identify ethnic differences in patterns of genetic testing. Methods: Results of all patients with known ancestry who underwent genetic testing at the hereditary breast and ovarian cancer center at a single institution between 7/1/2013-12/31/2016 were reviewed. Race was stratified as Black, White, Asian, and Hispanic. Ashkenazi Jews were excluded from the White subgroup because of their higher rates of testing for deleterious founder mutations. White patients were utilized as the reference population for all statistical analysis. Results: 894 patients were included: 139 Black, 613 White, 33 Hispanic and 108 Asian. Black patients were more likely to undergo genetic testing for a personal history of cancer rather than family history risk assessment compared to White patients (p = 0.002). There was no difference in genetic testing rates based on personal or family history of cancer between Asians or Hispanics and Whites (p = 0.398 ;p = 0.366). Black patients were more likely than White patients to undergo testing with targeted-gene rather than multigene panels (p = 0.026). The use of targeted and multigene panels were not different among Asians or Hispanics ( p = 1.0). Blacks, Asians and Hispanics had a lower rate of known deleterious mutations but a higher rate of variants of unknown significance (VUS) than Whites (15.1% p = 0.048; 22.2% p = .001; 33.3%p = .002 respectively). BRCA1/2 mutations accounted for 100% of identified mutations across all the non-White populations. Among Blacks, BRCA1/2 accounted for 38.1% of VUS compared to 27.9% in Whites ( p = .2114). VUS in the ATM gene accounted for 28.6% in Blacks compared to 8.2% in Whites (p = 0.028). Conclusions: Black patients were less likely to undergo testing based on family history, suggesting a missed opportunity for cancer prevention. They were more likely to undergo targeted testing and100% of identified mutations were in BRCA1/2 genes. Non-white patients had higher rates of VUS, emphasizing the need for improved VUS reclassification in non-White populations.