Serum perfluoroalkyl substances (PFASs) concentrations and associations with mammographic density in postmenopausal women.

Background

Perfluoroalkyl substances (PFASs) are possible carcinogens with widespread population exposure. Mammographic density (MD) is a biomarker of breast cancer risk that may offer important insights into potential mechanisms of breast carcinogenesis. Examining associations between PFAS exposure and MD may elucidate pathways by which PFASs could affect breast cancer risk. However, associations between PFAS exposure and MD remain poorly studied. We sought to evaluate associations of individual PFASs and their chemical mixture with percent mammographic density and dense breast area.

Methods

We analyzed data from 186 postmenopausal, cancer-free women not currently using hormone therapy from the Susan G. Komen Tissue Bank. Percent mammographic density (PMD) and dense breast area (DBA) were measured from digital mammography images taken near the time of blood sample donation. Serum PFAS concentrations were measured using online solid-phase extraction followed by high-pressure liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). Associations were examined using multivariable linear regression and Quantile g-computation.

Results

Participants had a mean age of 58.7 years and mean body mass index of 29.6 kg/m², and most were White (72.6%). The vast majority of mammograms were performed within 2 years of blood sample donation (88%). No statistically significant associations were observed with individual PFASs and either PMD or DBA in analyses adjusted for confounding variables. Quantile G-computation analyses did not identify a statistically significant effect of the PFAS mixture on PMD or DBA. Similar results were observed in analyses stratified by body mass index or breastfeeding history.

Conclusions

Overall, our study did not identify strong and significant associations between a panel of major PFASs and MD.