UCSF

Background

Risk of ovarian cancer in women with frequent perineal talcum powder product is not well understood. Prior systematic reviews focused on ever use. The purpose of this study is to estimate the association between frequent (at least 2 times per week) perineal talcum powder use and ovarian cancer.

Methods

A systematic review and meta-analysis was conducted according to meta-analysis of observational studies in epidemiology guidelines. Study protocol was prospectively registered at PROSPERO (registration number CRD42020172720). Searches were performed in PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials databases from their inception to August 2, 2021. Case-control and cohort studies were included if they reported frequent perineal talcum powder use and an adjusted odds ratio or hazard ratio for ovarian cancer. Review for inclusion, data extraction, and quality assessment (using the Newcastle-Ottawa Scale [NOS]) were performed independently by two reviewers. Pooled adjusted odds ratios with 95% confidence intervals were generated from the random effects model. Heterogeneity was quantified with I² statistic. Funnel plot and Eger's test were performed to assess publication bias. Subgroup and sensitivity analyses were performed for testing the robustness of the overall findings.

Results

Initial database searches returned 761 unique citations and after review, eleven studies describing 66,876 patients, and 6542 cancers were included (Cohen's κ = 0.88). Publication quality was high (median NOS = 8, range: 4 to 9). Frequent talcum powder use was associated with an elevated risk of ovarian cancer (adjusted pooled summary odds ratio 1.47 (95% CI 1.31, 1.65, P<0.0001). There was no evidence of bias and low heterogeneity (I²= 24%, P=0.22). There was no meaningful difference limiting analysis to publications with a NOS quality score of 8 or 9 or limiting studies based on study design.

Conclusions

This review suggests an increased risk of ovarian cancer associated with frequent perineal powder exposure of 31-65%.