Abstract PO-180: Genital powder use and risk of epithelial ovarian cancer in the Ovarian Cancer in Women of African Ancestry Consortium
Authors: Davis Colette P. , Bandera Elisa V. , Bethea Traci N. , Camacho Tareq F. , Joslin Charlotte E. , Wu Anna H. , Beeghly-Fadiel Alicia , Cloyd Emily K. , Moorman Patricia G. , Myers Evan , Ochs-Balcom Heather M. , Peres Lauren C. , Rosenow Will L. , Setiawan Veronica W. , Rosenberg Lynn , Schildkraut Joellen M , Harris Holly R. 
Published: December 2020

Abstract
PURPOSE: To date, the epidemiology of epithelial ovarian cancer (EOC) among African-American women has been severely understudied. It remains unclear to what extent variation in the prevalence of EOC risk factors may explain incidence disparities between African-American and white women. Genital powder use is more common among African-American women; however, studies of genital power use and EOC risk have been conducted predominantly in white populations, and histotype specific analyses among African-American populations are limited. The objective of this study was to evaluate the association between genital powder use and EOC risk among African-American and white women, overall and by histotype.
METHODS: We used data from four ovarian cancer case-control studies in the Ovarian Cancer in Women of African Ancestry (OCWAA) consortium: the African American Cancer Epidemiology Study, the Los Angeles County Ovarian Cancer Study, the Cook County Case-Control Study, and the North Carolina Ovarian Cancer Study. Participants included 601 African-American cases, 1,012 African-American controls, 2,225 white cases, and 3,086 white controls who answered questions on genital powder use prior to 2014. The association between genital powder use and EOC risk was estimated using logistic regression. Pooled histotype specific odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using polytomous logistic regression. The population attributable risk (PAR) by race was calculated using the Bruzzi method. RESULTS: The prevalence of reporting ever genital powder use was 66% among African-American women and 44% among white women. African- American women who ever used genital powder were 29% more likely to develop EOC compared to African-American women who reported no use (OR=1.29, 95% CI=0.98-1.71). White women who ever used genital powder were 36% more likely to develop EOC compared to white women reporting no use (OR=1.36, 95% CI=1.12- 1.52). The associations were similar when examined by histotype. Among African- American women, the ORs were 1.29 (95% CI=0.94-1.76) for high grade serous (HGS) and 1.38 (95% CI=0.87-2.19) for non-HGS. For white women, the corresponding ORs were 1.27 (95% CI=1.06-1.52) and 1.21 (95% CI=0.96-1.56), respectively. The PAR for genital powder use was slightly higher, but not statistically significantly different, in African-American women (PAR=10.7, 95% CI=3.7-17.5) compared to white women (PAR=7.8, 95% CI=4.9-10.7). CONCLUSION: While the prevalence of ever genital body powder use was higher among African-American women, the associations between genital powder use and ovarian cancer risk were similar between African-American and white women, and did not materially vary by histotype. Further analyses incorporating additional OCWAA studies and using more refined exposure categories (e.g., frequency and duration of powder use, age at first application) are currently being conducted.
Citation Format: Colette P. Davis, Elisa V. Bandera, Traci N. Bethea, Tareq F. Camacho, Charlotte E. Joslin, Anna H. Wu, Alicia Beeghly-Fadiel, Emily K. Cloyd, Patricia G. Moorman, Evan Myers, Heather M. Ochs-Balcom, Lauren C. Peres, Will L. Rosenow, Veronica W. Setiawan, Lynn Rosenberg, Joellen M Schildkraut, Holly R. Harris. Genital powder use and risk of epithelial ovarian cancer in the Ovarian Cancer in Women of African Ancestry Consortium [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-180.