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Mammographic breast density, hormones, and growth factors during continuous combined hormone therapy
Peter Conner1, Gunilla Svane, Edward Azavedo
1Department of Obstetrics and Gynecology, Karolinska Hospital, Stockholm, Sweden. peter.conner@ks.se
Objective:
To study the effect on mammographic breast density of two different continuous combined regimens for hormone therapy.
Design:
Randomized clinical study.
Setting:
University hospital.
Patient(S):
Postmenopausal women without any previous history of breast disorder.
Intervention(S):
The women received either estradiol valerate/dienogest or estradiol/norethisterone acetate. Mammograms and venous blood samples were obtained at baseline and after 6 months.
Main Outcome Measure(S):
Change in mammographic breast density. Correlations with levels of hormones, growth factors, and binding proteins.
Result(S):
An increase in mammographic density was recorded in approximately 50% of the women, and there were no differences between treatments. Increased density showed a positive correlation with estradiol, estrone, and sex hormone-binding globulin and showed a negative association to free T. Among hormonal factors, levels of free T were the most important for predicting increased density.
Conclusion(S):
Continuous combined hormone therapy with different progestogens has a marked impact on the breast.
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