Douching, Talc Use, and Risk of Ovarian Cancer

Abstract

Background Douching was recently reported to be associated with elevated levels of urinary metabolites of endocrine disrupting phthalates, but there is no literature on douching in relation to ovarian cancer. Numerous case-control studies of genital talc use have reported an increased risk of ovarian cancer, but prospective cohort studies have not uniformly confirmed this association. Behavioral correlation between talc use and douching could produce confounding. Methods The Sister Study (2003–2009) enrolled and followed 50,884 women in the US and Puerto Rico who had a sister diagnosed with breast cancer. At baseline participants were asked about douching and talc use during the previous 12 months. During follow-up (median of 6.6 years) 154 participants reported a diagnosis of ovarian cancer. We computed adjusted hazard ratios (HR) and 95% confidence intervals (CI) for ovarian cancer risk using the Cox proportional hazards model. Results There was little association between baseline perineal talc use and subsequent ovarian cancer (HR: 0.73 CI: 0.44, 1.2). Douching was more common among talc users (OR: 2.1 CI: 2.0, 2.3), and douching at baseline was associated with increased subsequent risk of ovarian cancer (HR: 1.9 CI: 1.2, 2.8). Conclusions Douching but not talc use was associated with increased risk of ovarian cancer in the Sister Study.

Racial health disparities in ovarian cancer: not just black and white

“…A prospective study that followed 61,576 post-menopausal women for 12.4 years, however, could not link talc use with OC risk [ 76 ]. The results were confirmed by another independent study which found douching, and not talc use, as a risk factor for OC [ 77 ]. A recent meta-analysis, however, confirmed risk of OC from genital talc use with a statistically significant risk of serous OC [ 78 ].…”

Talc, Asbestos, and Epidemiology: Corporate Influence and Scientific Incognizance

“…At least 32 epidemiologic studies have examined the relation between talcum powder usage and ovarian cancer. 20,37–67 Twelve out of the 32 epidemiologic studies of talc and ovarian cancer incorporated the Cosmetic, Toiletry, and Fragrance Association’s claim that “cosmetic” talc has been free of asbestos since 1976. 38–40,43,45,47,48,56,57,59,61,64 The association between asbestos inhalation and ovarian cancer was noted in 1949, again in 1960, 68,69 and again in 1982.…”

“…Three of the investigations were planned as prospective cohort studies and talc exposure was only evaluated once; thus, the studies did not prospectively evaluate talc exposure over time. 56,59,67 Also, given that the induction period and latency for ovarian cancer is between 25 and 40 years, 67 none of the study cohorts had sufficient follow-up time. 56,59,64,67 Gertig et al (Nurses’ Health Study) stated that, “Our relatively short follow-up period may be inadequate to detect an association if the latency for development of ovarian cancer is more than 15 years.” 56 Ten years later, Gates et al updated the Nurses’ Health Study talc use results, comparing rates of ovarian cancer between two groups of talc users (>1 week to <1 week) and found a near null rate ratio of 1.06 (95% CI = 0.89, 1.28).…”

“…64 The “Sister Study” follow-up had a median induction period and latency of 6.6 years. 67 Further, a number of studies (including all three “prospective” cohort studies) conflated cornstarch and talc cosmetic powders, leading to additional exposure misclassification. 56,59,64,67 Customer product false recognition and recall may have led to additional misclassification.…”

“…67 Further, a number of studies (including all three “prospective” cohort studies) conflated cornstarch and talc cosmetic powders, leading to additional exposure misclassification. 56,59,64,67 Customer product false recognition and recall may have led to additional misclassification. For example, there are two different types of Johnson & Johnson powder products (talcum and cornstarch) and Johnson & Johnson has had the highest share of the total baby powder market.…”