The effect of low dose hormone therapy on mammographic breast density.
OBJECTIVE
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.
Christodoulakos
George E
GE
2nd Department of Obstetrics and Gynecology, University of Athens, Aretaieion Hospital, 27, Themistokleous Street, Dionysos, GR-14578 Athens, Greece.
Lambrinoudaki
Irene V
IV
Vourtsi
Athina D
AD
Vlachou
Sofia
S
Creatsa
Maria
M
Panoulis
Konstantinos P C
KP
Botsis
Dimitrios
D
D000328:Adult; D000368:Aged; D001940:Breast / Q000187:drug effects*; D003271:Contraceptive Agents, Female / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000008:administration & dosage; D015914:Estrogen Replacement Therapy / Q000379:methods*; D004967:Estrogens / Q000008:administration & dosage; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008327:Mammography; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage; D008875:Middle Aged; D009640:Norethindrone / Q000008:administration & dosage / Q000031:analogs & derivatives; D000077563:Norethindrone Acetate; D017698:Postmenopause
D003271:Contraceptive Agents, Female; D004967:Estrogens; D004966:Estrogens, Conjugated (USP); D004958:Estradiol; D000077563:Norethindrone Acetate; D017258:Medroxyprogesterone Acetate; D009640:Norethindrone