عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Background & Objective : Nowadays breast cancer is one of the most causes of female mortality. Mammography is a valuable method for early detection of breast cancer. Mammographic sensitivity depends on some factors such as age, breast tissue density, menopausal status, systemic disease, familial history of breast cancer and others. This study was designed to compare the effects of two regimens of hormone replacement therapy (HRT) on mammographic density. Materials & Methods: 110 postmenopausal women under hormone replacement therapy who had been referred to the service of mammography were selected. On the basis of type of HRT, women were divided into two groups: 1) Continuous conjugated estrogen plus daily medroxy progesterone acetate (80 cases) and 2) daily conjugated estrogen plus sequentially medroxy progesterone acetate 2 weeks per month (30 cases). All of the women had a baseline mammogram before the onset of HRT which was comparing with control mammograms during treatment. Results: Control mammograms reveals increased breast density in 45% of the first group members and in 13.3% of the other group, which was statistically significant (p < 0.05) Conclusion: Hormone replacement therapy can increase mammographic density which is more prominent with continuous and daily estrogen and progesterone regimens.