title: The association of endogenous sex steroids and sex steroid binding proteins with mammographic density: results from the Postmenopausal Estrogen/Progestin Interventions Mammographic Density Study.
abstract: Mammographic density is an independent risk factor for breast cancer. In postmenopausal women, higher levels of endogenous sex steroids are associated with an increased risk of breast cancer. Limited prior data suggest that endogenous sex steroids either are not associated (total estradiol and progesterone) or are negatively associated (free estradiol) with higher mammographic density. To analyze the associations between endogenous sex steroids and mammographic density, the authors conducted a 1998-2005 cross-sectional analysis of baseline clinical trial data from the Postmenopausal Estrogen/Progestin Interventions (PEPI) Trial for US women who had not used hormone therapy for at least 3.1 months prior to baseline. In models adjusted for age, body mass index, parity, prior use of hormone therapy, time since last use of hormone therapy, and the interaction between prior hormone therapy use and time since last hormone therapy use, higher levels of estrone (beta = 0.0013, p = 0.014), estradiol (beta = 0.0009, p = 0.009), and bioavailable estradiol (beta = 0.0021, p = 0.018) were statistically significantly related to greater mammographic density. (Beta coefficients express the increment in mammographic density per-unit increment (pg/ml) of each hormone.) These results suggest that some sex steroids may increase the risk of breast cancer by stimulating breast epithelial or stromal proliferation, which appears on a mammogram as higher density.
authors.affiliation: Division of Geriatrics, David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90095-1687, USA. ggreenda@mednet.ucla.edu
authors.forename: Gail A
authors.initials: GA
authors.lastname: Greendale
authors.forename: Shana L
authors.initials: SL
authors.lastname: Palla
authors.forename: Giske
authors.initials: G
authors.lastname: Ursin
authors.forename: Gail A
authors.initials: GA
authors.lastname: Laughlin
authors.forename: Carolyn
authors.initials: C
authors.lastname: Crandall
authors.forename: Malcolm C
authors.initials: MC
authors.lastname: Pike
authors.forename: Beth A
authors.initials: BA
authors.lastname: Reboussin
mesh_terms: D001940:Breast / Q000033:anatomy & histology*; D001943:Breast Neoplasms / Q000209:etiology; D003430:Cross-Sectional Studies; D045166:Estradiol Congeners / Q000097:blood; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood*; D011374:Progesterone / Q000097:blood; D012307:Risk Factors; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism*; D013739:Testosterone / Q000097:blood; D014481:United States
chemical_list: D045166:Estradiol Congeners; D012739:Gonadal Steroid Hormones; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D011374:Progesterone