Breast density and cancer

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

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.

Mammographic density increase in women receiving different hormone replacement regimens

OBJECTIVE

we investigated effects of different regimens of hormone replacement therapy (HRT) on mammographic density.

METHODS

ninety-five postmenopausal women, who were on different HRT regimens and completed their 4-year mammographic follow-up, were included into this retrospective and comparative study. Twenty-three of these women, who had surgical menopause, received conjugated equine estrogens (CEE) (Group I) only, 26 of them received CEE and continuous medroxyprogesterone acetate (MPA) (Group II), 21 women received CEE and cyclic MPA (Group III), and the remaining 25 women received tibolone (Group IV) therapy. Before commencing on HRT, a baseline high-resolution mammography was performed, and repeated at 6-12-month intervals during the period of 4-year follow-up. All mammographies were evaluated according to the Wolfe classification.

RESULTS

a diffuse increase in mammographic density was detected in five women (22%) in group I, nine women (35%) in group II, four women (19%) in group III, and two women (8%) in group IV. The increase in mammographic density was more common among women in group II than those in the other three groups. However, a statistically significant difference was found only between groups II and IV.

CONCLUSIONS

different HRT regimens have different effects on breast parenchymal density on mammography. Continuous combination HRT may be more commonly associated with an increase in breast density than other forms of HRT.

Mammographic breast density during hormone replacement therapy: differences according to treatment

OBJECTIVE

Our purpose was to investigate the effects of various hormone replacement regimens on mammographic breast density.

STUDY DESIGN

Mammographic density was recorded in women participating in a population-based screening program. All women were nonusers of hormone replacement therapy at first mammogram and thereafter reported continuous use of the same treatment: estrogen alone (n = 50) or estrogen in cyclic (n = 75) or continuous (n = 50) combination with progestogen. Mammographic density was quantified according to the Wolfe classification.

RESULTS

An increase in mammographic density was much more common among women receiving continuous combination hormone replacement therapy (52%) than among those receiving cyclic (13%) and estrogen-only (18%) treatment. The increase in density was apparent already at first visit after the start of hormone replacement therapy. There was little change in mammographic status during long-term follow-up.

CONCLUSION

Regimens of hormone replacement therapy were shown to have different effects on the normal breast. There is an urgent need to clarify the biologic nature and significance of a change in mammographic density during treatment and, in particular, its relation to symptoms and breast cancer risk.