Use of genital powder use is more common among Black women than White women, but previous studies of genital powder use and ovarian cancer risk have been primarily been conducted in White populations. Women usually report genital powder use in the form of baby or feminine powder for cleanliness, freshness, and dryness of the genital region. Talc is a common ingredient in many genital powders and has been suggested to play a role in ovarian cancer development, although uncertainty about this association still exists. Beginning in 2014, several lawsuits were filed against companies with talc products on behalf of women with ovarian cancer. The study with the largest number of Black ovarian cancer cases to examine the association with genital powder use was a pooled analysis which combined the African American Cancer Epidemiology Study (AACES) with 7 case-control studies from the Ovarian Cancer Association Consortium (OCAC) with information on genital powder use. However, this study examined heterogeneity across all racial groups (i.e. was not focused on comparing Black and White women) and did not examine associations by frequency or duration of genital powder use. Thus, the objective of the present study by the Harris Group, Division of Public Health Sciences, was to evaluate the association between genital powder use and epithelial ovarian cancer risk among Black and White women in the Ovarian Cancer in Women of African Ancestry (OCWAA) consortium overall, by histotype, and examining frequency and duration. These analyses improve on prior studies due to OCWAAs inclusion of studies with at least 40 Black women with ovarian cancer which provides the ability to assess heterogeneity across studies while its exclusion of cases diagnosed prior to 2013 lessens the potential impact of recall bias. This study was published in Cancer Epidemiology, Biomarkers & Prevention: a Publication of the American Association for Cancer Research.
In this analysis, four population-based case-control studies (the North Carolina Ovarian Cancer Study [NCOCS], Los Angeles County Ovarian Cancer Study [LACOCS], Cook County Case Study [CCCS], and African American Cancer Epidemiology Study [AACES]), and a nested case-control study within the Women’s Health Initiative [WHI] Observational Study were included. Eligibility was restricted to interview year prior to 2014 for case-control studies to reduce recall bias following the class action lawsuits that were filed in 2014. Data on cancer diagnoses were abstracted from medical records and cancer registry reports. Ever use and duration of genital body powder use was assessed in all studies while frequency of use was assessed in four studies. Frequency of genital powder use was categorized as no use, ≤once per week, and >once per week. Duration of genital powder use was categorized as no use, <20 years, and ≥20 years. Race and study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were combined using a multi-level random-effects meta-analysis. As no significant heterogeneity by study was detected, random effects were removed from the model and data from the individual studies was pooled. The association between each genital powder variable (ever use, frequency, and duration) and ovarian cancer risk was estimated using logistic regression models. The population attributable risk (PAR) for ever use of genital powder overall and by race was estimated using the Bruzzi method.
Ever use of genital powder was associated with 32% higher risk of ovarian canceramong all women (pooled OR=1.32; 95% CI=1.17-1.48). When stratified by race, there was a 36% higher risk of ovarian cancer among White women (pooled OR=1.36; 95% CI=1.19-1.57) and a non-significant higher risk among Black women (pooled OR=1.22; 95% CI=0.97-1.53). In terms of cancer histotype, both Black and White women who ever used powder in the genital area were at a higher risk for high-grade serous ovarian cancer (Black women OR=1.31; 95% CI=1.01-1.71, White women OR=1.33; 95% CI=1.12-1.56). No difference in the association was observed by frequency of genital powder use once per week and more than once per week. When frequency was examined by race a similar pattern was observed. No dose-response trends were observed for duration of genital powder use overall or when stratified by race. The PARs for ever use of genital body powder were similar between Black women (7.5%;95% CI= 6.5%-8.5% and White women (6.2%; 95% CI=5.4%-6.9%). The PAR when Black and White women were combined was 6.4% (95% CI=2.2%-10.0%).
In this study, ever use of genital body powder was associated with higher odds of ovarian cancer in both Black and White women and the population attributable risk was similar in the two groups. Use of genital body powder was more strongly associated with the risk of high grade serous cancer than with non-high-grade serous cancer in Black women, while a positive association was observed irrespective of histotype in White women. There was not a dose response relationship regarding frequency or duration of genital powder use and ovarian cancer among Black or White women. According to Dr. Davis, the first author of the paper, “To our knowledge this is only the second study to examine the association between frequency and duration of genital powder use and ovarian cancer risk among Black women. Also, very few studies have examined the PAR for genital body powder use and ovarian cancer by race”.
This research was supported by the National Institutes of Health.
Fred Hutch/UW Cancer Consortium member Holly R. Harris contributed to this work.
Davis CP, Bandera EV, Bethea TN, Camacho F, Joslin CE, Wu AH, Beeghly-Fadiel A, Moorman PG, Myers ER, Ochs-Balcom HM, Peres LC, Rosenow WT, Setawan VW, Rosenberg, L, Schildtkraut JM and Harris HR. Genital powder use and risk of epithelial ovarian cancer in the Ovarian Cancer in Women of African Ancestry Consortium. Cancer Epidemiology and Prevention Biomarkers. 2021 Jan 1. DOI: 10.1158/1055-9965.EPI-21-0162