Mammographic density as a risk factor of breast cancer

Mammographic density refers to the presence of fibroglandular tissue in the breast. Several studies including our study in which quantitative methods of were used for assessing breast density have demonstrated a positive association with breast cancer risk. Most studies yielded an odds ratio of 4 or greater for the most dense compared with the least dense breast tissue category. Mammographic density is of interest in assessing the etiology of breast cancer, but it may also have potential as a surrogate marker of risk in interventions designed to reduce the risk of breast cancer.