title: Associations of sex steroid hormones with mortality in women with breast cancer.
abstract: Epidemiological studies have demonstrated associations between circulating levels of sex steroid hormones and risk of breast cancer in postmenopausal women. However, data on associations with breast cancer survival are limited. We measured levels of estradiol, estrone, testosterone, and sex hormone-binding globulin (SHBG), in serum collected on average 30 months after diagnosis from 358 postmenopausal women diagnosed with stage I-IIIA breast cancer between 1995 and 1998 who participated in a multiethnic, prospective cohort study. Women were followed through December, 2012. We evaluated associations between log-transformed analytes and breast cancer-specific and all-cause mortality fitting multivariable Cox proportional hazards models. Over a median of 14.5 years of follow-up, 102 deaths occurred; 43 of these were due to breast cancer. In models adjusted for ethnicity/study site, age, body mass index, and tumor stage, increased levels of log-transformed SHBG were associated with reduced risk of both breast cancer-specific mortality (hazard ratio, HR 0.48; 95 % confidence interval, CI 0.26-0.89) and all-cause mortality (HR 0.64, 95 % CI 0.43-0.97). There were no associations between levels of estradiol, estrone, or testosterone for either endpoint. In subgroup analyses, after correction for multiple testing, increased estrone was significantly associated with reduced risk for breast cancer-specific mortality among participants with ER-negative tumors (HR 0.16, 95 % CI 0.05-0.63) but not among participants with ER-positive tumors. Increased serum levels of SHBG were associated with decreased risk of breast cancer-specific and all-cause mortality in women with breast cancer. These results should be confirmed in larger breast cancer survivor cohorts.
authors: Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. cduggan@fhcrc.org.
authors: Catherine
authors: C
authors: Duggan
authors: Department of Obstetrics, Gynecology, and Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
authors: Frank
authors: F
authors: Stanczyk
authors: Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
authors: Kristin
authors: K
authors: Campbell
authors: Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
authors: Marian L
authors: ML
authors: Neuhouser
authors: Department of Epidemiology and Population Health, School of Public Health and Information Sciences, James Graham Brown Cancer Center, University of Louisville, Louisville, KY, USA.
authors: Richard N
authors: RN
authors: Baumgartner
authors: Department of Epidemiology and Population Health, School of Public Health and Information Sciences, James Graham Brown Cancer Center, University of Louisville, Louisville, KY, USA.
authors: Kathy B
authors: KB
authors: Baumgartner
authors: Department of Population Sciences, Division of Cancer Etiology, Beckman Research Institute of the City of Hope, Duarte, CA, USA.
authors: Leslie
authors: L
authors: Bernstein
authors: Office of Disease Prevention, National Institutes of Health, Bethesda, MD, USA.
authors: Rachel
authors: R
authors: Ballard
authors: Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.|University of Washington Schools of Public Health and Medicine, Seattle, WA, USA.
authors: Anne
authors: A
authors: McTiernan
mesh_terms: D000328:Adult; D000735:Androstenedione / Q000097:blood; D001943:Breast Neoplasms / Q000097:blood* / Q000401:mortality* / Q000473:pathology; D004958:Estradiol / Q000097:blood; D004970:Estrone / Q000097:blood; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D017698:Postmenopause / Q000097:blood; D016016:Proportional Hazards Models; D012738:Sex Hormone-Binding Globulin / Q000096:biosynthesis; D013739:Testosterone / Q000097:blood
chemical_list: D012739:Gonadal Steroid Hormones; D012738:Sex Hormone-Binding Globulin; D004970:Estrone; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol
keywords: Breast cancer; Mortality; Sex steroid hormones