Mammographic density and its interaction with other breast cancer risk factors in an Asian population

Abstract

Background: Joint effects of mammographic density and other risk factors on breast cancer risk remain unclear. Methods: From The Singapore Breast Screening Project, we selected 491 cases and 982 controls. Mammographic density was measured quantitatively. Data analysis was by conditional logistic regression. Results: Density was a significant risk factor, adjusting for other factors. Density of 76-100% had an odds ratio of 5.54 (95% CI 2.38-12.90) compared with 0-10%. Density had significant interactions with body mass index and oral contraceptive use (P=0.02).Conclusions:Percent density increases breast cancer risk in addition to effects of other risk factors, and modifies the effects of BMI and OCs. © 2011 Cancer Research UK All rights reserved.