Hormone Therapy Associated With Increased Breast Density
A new study suggests that the use of combination hormone therapy is associated with a modest increase in breast density, which is a known risk factor for breast cancer. The findings appear in the Jan. 1 issue of the Journal of the National Cancer Institute. The degree of breast-cancer risk that is associated with breast density is greater than that associated with almost all other known breast-cancer risk factors. A previous analysis of data from the Postmenopausal Estrogen/Progestin Interventions (PEPI) Trial, a randomized trial looking at the effects of postmenopausal hormone therapy (estrogen alone or estrogen plus three different progestin regimens) on breast density, showed that some women who used combination estrogen/progestin therapy experienced an increase in breast density. However, the analysis did not look at the magnitude of that increase.