Genital Powder Use and Risk of Epithelial Ovarian Cancer in the Ovarian Cancer in Women of African Ancestry Consortium

Abstract

Background: Genital powder use is more common among African-American women; however, studies of genital powder use and ovarian cancer risk have been conducted predominantly in White populations, and histotype-specific analyses among African-American populations are limited. Methods: We used data from five studies in the Ovarian Cancer in Women of African Ancestry consortium. Participants included 620 African-American cases, 1,146 African-American controls, 2,800 White cases, and 6,735 White controls who answered questions on genital powder use prior to 2014. The association between genital powder use and ovarian cancer risk by race was estimated using logistic regression. Results: The prevalence of ever genital powder use for cases was 35.8% among African-American women and 29.5% among White women. Ever use of genital powder was associated with higher odds of ovarian cancer among African-American women [OR = 1.22; 95% confidence interval (CI) = 0.97–1.53] and White women (OR = 1.36; 95% CI = 1.19–1.57). In African-American women, the positive association with risk was more pronounced among high-grade serous tumors (OR = 1.31; 95% CI = 1.01–1.71) than with all other histotypes (OR = 1.05; 95% CI = 0.75–1.47). In White women, a significant association was observed irrespective of histotype (OR = 1.33; 95% CI = 1.12–1.56 and OR = 1.38; 95% CI = 1.15–1.66, respectively). Conclusions: While genital powder use was more prevalent among African-American women, the associations between genital powder use and ovarian cancer risk were similar across race and did not materially vary by histotype. Impact: This is one of the largest studies to date to compare the associations between genital powder use and ovarian cancer risk, overall and by histotype, between African-American and White women.

Intimate Care Products and Incidence of Hormone-Related Cancers: A Quantitative Bias Analysis

“…Pooled analyses or meta-analyses of case-control studies have produced odds ratios of 1.2-1.4. [33][34][35][36][37] The HR from a pooled analysis of prospective cohort studies 21 also indicated a positive, albeit small association (HR 5 1.08), and as previously noted, this effect estimate is likely biased toward the null because of nondifferential misclassification of exposure. This possibility is well illustrated by the Sister Study, where we previously reported 27% ever use of genital talc, 21 but here observe 40% ever use across a wider age range.…”

Epidemiologic Methods to Advance Our Understanding of Ovarian Cancer Risk

“…The use of intimate care products is a relatively common practice among women, with estimates of use in more than 50% in some populations. [1][2][3][4][5][6] Use of these products, including genital powder and douching, has been shown to vary across multiple factors including age, race, ethnicity, body size, and socioeconomic status. 3,4,7,8 These products are used for a variety of reasons including cleanliness, freshness, odor removal, and dryness of the genital region.…”

“…Pooled analyses of case-control studies have shown estimates of 24%-32% higher ovarian cancer risk for ever compared with never use of genital powder, as well as the suggestion of higher risk with increasing number of lifetime applications. 2,5 However, cohort studies, which have less detailed data on powder exposure (leading to nondifferential misclassification), have provided more ambiguous results, with limited power to detect modest associations even when data are pooled across studies. [12][13][14][15] Thus, given these previously identified differences by study design, 16,17 additional methods are necessary to more clearly understand the impacts of this common exposure on gynecologic and hormone-associated cancer outcomes.…”