Assessment of mammographic density in postmenopausal women during long term hormone replacement therapy

Abstract

Objective: To assess long-term effects of different hormone replacement therapy (HRT) regimens on mammographic density.

Methods: One hundred sixty-five postmenopausal women were treated with the same HRT during 5 years: 38 received transdermal estradiol, 78 cyclic combined therapy and 49 continuous combined therapy. Mammograms were obtained at baseline, at 1-year and 5-year treatment. Breast density changes were categorized as slight focal increased density, considerable focal increased density, slight diffuse increased density and considerable diffuse increased density.

Results: Mammographic density increased in 7.9% of women receiving estrogen alone versus 25.2% of women receiving combined therapy (p < 0.022) during 1 year, and in 7.9% of women versus 28.3% of women (p < 0.009) after 5 years of therapy, respectively. There were significant statistical differences in women treated with estrogen alone versus those treated with combined HRT after 1 and 5 years. After 5 years of HRT, breast density increased 21.8% in women receiving cyclic combined therapy versus 38.8% in those under continuous combined therapy (p < 0.039).

Conclusion: An increase in breast density is significantly more frequent in women receiving combined estrogen-progestin therapy than in women receiving estrogen alone. There are differences between cyclic and continuous combined therapy at 5 years of treatment.

• Breast density
• hormonal replacement therapy
• mammogram
• medroxyprogesterone acetate
• transdermal estradiol

Notice of Correction

The version of this article published online ahead of print on 04 Sep 2013 contained an error in the list of authors. The first author “Encarnación Carmona-Sánchez” was incorrectly listed with the surname “Sánchez” and it should have been “Carmona-Sánchez”. As a result, the name in the header of pages 2 and 4 should read “E. Carmona-Sánchez” and not “E. C. Sánchez”. The error has been corrected for this version.