Association of daily alcohol intake, volumetric breast density, and breast cancer risk
Menée aux Etats-Unis à partir de données portant sur 4 562 témoins et 2 233 patientes atteintes d'un cancer du sein diagnostiqué entre 2006 et 2013, cette étude analyse le rôle de la densité mammaire dans l'association entre la consommation quotidienne d'alcool et le risque de développer la maladie
High alcohol intake and breast density increase breast cancer (BC) risk, but their interrelationship is unknown. We examined whether volumetric density modifies and/or mediates the alcohol-BC association. BC cases (n = 2233) diagnosed from 2006–2013 in the San Francisco Bay Area had screening mammograms ≥6 months before diagnosis; controls (n = 4562) were matched on age, mammogram date, race/ethnicity, facility, and mammography machine. Logistic regression was used to estimate alcohol-BC associations, adjusted for age, body mass index, and menopause; interaction terms assessed modification. Percent mediation was quantified as the ratio of log(odds ratios [ORs]) from models with and without density measures. Alcohol consumption was associated with increased BC risk (two-sided p-trend = 0.004), as were volumetric percent density (OR = 1.45 per SD, 95%CI = 1.36–1.56) and dense volume (OR = 1.30, 95%CI = 1.24–1.37). Breast density did not modify the alcohol-BC association (two-sided p > .10 for all). Dense volume mediated 25.0% (95%CI = 5.5%–44.4%) of the alcohol-BC association (two-sided p = .01), suggesting alcohol may partially increase BC risk by increasing fibroglandular tissue.
JNCI Cancer Spectrum 2021