title: The effect of various regimens of hormone replacement therapy on mammographic breast density.
abstract: OBJECTIVE
  To evaluate the effect of three distinct hormone replacement therapy regimens on mammography.
  
  
  METHODS
  121 postmenopausal women who had never received or were past users of hormone replacement therapy were studied prospectively. Women with an intact uterus were randomly allocated either to conjugated equine estrogens 0.625 mg plus medroxyprogesterone acetate 5 mg (CEE/MPA, n=34) or to 17beta-estradiol 2 mg plus norethisterone acetate 1 mg (E(2)/NETA, n=35). Hysterectomized women received CEE 0.625 mg (CEE, n=25). Women who either declined or did not qualify for treatment served as controls (n=27). 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
  No increase in breast density was identified in any of the women in the control group. Two women (8%) in the CEE group showed an increase in breast density. Four women (11.8%) in the CEE/MPA and 11 women (31.4%) in the E(2)/NETA group revealed an increase in breast density. No woman in the therapy groups showed an involution of fibroglandular tissue while seven women (25.9%) in the control group exhibited involution of breast parenchyma.
  
  
  CONCLUSIONS
  Our study suggests that hormone replacement therapy may suspend breast involution but does not increase breast density in the majority of patients. In the minority of patients who show a density increase, the magnitude of this increase varies according to the regimen employed.
authors.affiliation: 2nd Department of Obstetrics and Gynecology, Aretaieion Hospital, University of Athens, 3, Neofytou Douka Street, GR-10674, Athens, Greece. ilambrinoudaki@hotmail.com
authors.forename: George E
authors.initials: GE
authors.lastname: Christodoulakos
authors.forename: Irene V
authors.initials: IV
authors.lastname: Lambrinoudaki
authors.forename: Konstantinos P C
authors.initials: KP
authors.lastname: Panoulis
authors.forename: Athina D
authors.initials: AD
authors.lastname: Vourtsi
authors.forename: L
authors.initials: L
authors.lastname: Vlachos
authors.forename: E
authors.initials: E
authors.lastname: Georgiou
authors.forename: George C
authors.initials: GC
authors.lastname: Creatsas
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000187:drug effects*; D004334:Drug Administration Schedule; D004958:Estradiol / Q000008:administration & dosage / Q000494:pharmacology; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage / Q000494:pharmacology; D005260:Female; D006801:Humans; D008327:Mammography; D008525:Medroxyprogesterone / Q000008:administration & dosage / Q000494:pharmacology; D008875:Middle Aged; D009640:Norethindrone / Q000008:administration & dosage / Q000494:pharmacology; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D004966:Estrogens, Conjugated (USP); D004958:Estradiol; D008525:Medroxyprogesterone; D009640:Norethindrone