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The effect of low dose hormone therapy on mammographic breast density
George E Christodoulakos1, Irene V Lambrinoudaki, Athina D Vourtsi
12nd Department of Obstetrics and Gynecology, University of Athens, Aretaieion Hospital, 27, Themistokleous Street, Dionysos, GR-14578 Athens, Greece.
Objectives:
To evaluate the effect of two standard and one low dose continuous hormone therapy regimens on mammography.
Methods:
One hundred and thirty-two non-hysterectomized postmenopausal women were randomly allocated either to conjugated equine estrogens 0.625 mg plus medroxyprogesterone acetate 5 mg (CEE/MPA, n=38), 17beta-estradiol 2 mg plus norethisterone acetate 1 mg (E2/NETA, n=44) or 17beta-estradiol 1 mg plus norethisterone acetate 0.5 mg (low E2/NETA, n=50). Treatment was continuous and the study period lasted 12 months. Main outcome measures were the changes according to Wolfe classification between baseline and 12-month mammograms.
Results:
Five (13.2%) women in the CEE/MPA group showed an increase in breast density. Fourteen (31.8%) women on E2/NETA and 6 (12.2%) on low E2/NETA treatment revealed an increase in breast density. No woman exhibited an involution of fibroglandular tissue.
Conclusions:
Different hormone therapy regimens have a variable impact on breast density probably depending on the steroid used. Low dose hormone therapy associates with significantly lesser increase in breast density.
