title: Mammographic densities as a marker of human breast cancer risk and their use in chemoprevention.
abstract: Differences in the parenchymal pattern of the breast on mammography reflect differences in the amounts of stromal, epithelial, and fat tissue present in the breast. Stroma and epithelium are radiologically dense, whereas fat is lucent. Extensive areas of mammographically dense breast tissue are strongly associated with an increased risk of breast cancer. A variety of interventions, including gonadotropin-releasing hormone inhibitor, tamoxifen, stopping hormone replacement therapy (HRT), and adopting a low-fat, high-carbohydrate diet, all influence the tissue composition of the breast and reduce mammographic densities. Of the interventions examined to date, only tamoxifen has been shown to reduce the incidence of breast cancer, at least in the short term. Conversely, HRT, which increases density, also increases risk of breast cancer. These results suggest that mammographic density may be a short-term marker of the effect on the breast of potential preventive interventions for breast cancer.
authors.affiliation: Division of Epidemiology and Statistics, Ontario Cancer Institute, Room 10-415, 610 University Avenue, Toronto, ON, Canada M5G 2M9.
authors.forename: N F
authors.initials: NF
authors.lastname: Boyd
authors.forename: L J
authors.initials: LJ
authors.lastname: Martin
authors.forename: J
authors.initials: J
authors.lastname: Stone
authors.forename: C
authors.initials: C
authors.lastname: Greenberg
authors.forename: S
authors.initials: S
authors.lastname: Minkin
authors.forename: M J
authors.initials: MJ
authors.lastname: Yaffe
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy; D018890:Chemoprevention / Q000379:methods*; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D012307:Risk Factors; D013629:Tamoxifen / Q000008:administration & dosage
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D013629:Tamoxifen