title: Plasma sex hormone concentrations and breast cancer risk in an ethnically diverse population of postmenopausal women: the Multiethnic Cohort Study.
abstract: To add to the existing evidence that comes mostly from White populations, we conducted a nested case-control study to examine the association between sex hormones and breast cancer risk within the Multiethnic Cohort that includes Japanese American, White, Native Hawaiian, African American, and Latina women. Of the postmenopausal women for whom we had a plasma sample, 132 developed breast cancer during follow-up. Two controls per case, matched on study area (Hawaii, Los Angeles), ethnicity/race, birth year, date and time of blood draw and time fasting, were randomly selected from the women who had not developed breast cancer. Levels of estradiol (E(2)), estrone (E(1)), androstenedione, dehydroepiandrosterone (DHEA), and testosterone were quantified by RIA after organic extraction and Celite column partition chromatography. E(1) sulfate, DHEA sulfate (DHEAS), and sex hormone-binding globulin (SHBG) were quantified by direct immunoassays. Based on conditional logistic regression, the sex hormones were positively associated and SHBG was negatively associated with breast cancer risk. All associations, except those with DHEAS and testosterone showed a significant linear trend. The odds ratio (OR) associated with a doubling of E(2) levels was 2.26 (95% confidence interval (CI) 1.58-3.25), and the OR associated with a doubling of testosterone levels was 1.34 (95% CI 0.98-1.82). The associations in Japanese American women, who constituted 54% of our sample, were similar to or nonsignificantly stronger than in the overall group. This study provides the best evidence to date that the association between sex hormones and breast cancer risk is generalizable to an ethnically diverse population.
authors.affiliation: Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii, 1236 Lauhala Street, Honolulu, Hawaii 96813, USA. cwoolcott@crch.hawaii.edu
authors.forename: Christy G
authors.initials: CG
authors.lastname: Woolcott
authors.forename: Yurii B
authors.initials: YB
authors.lastname: Shvetsov
authors.forename: Frank Z
authors.initials: FZ
authors.lastname: Stanczyk
authors.forename: Lynne R
authors.initials: LR
authors.lastname: Wilkens
authors.forename: Kami K
authors.initials: KK
authors.lastname: White
authors.forename: Christian
authors.initials: C
authors.lastname: Caberto
authors.forename: Brian E
authors.initials: BE
authors.lastname: Henderson
authors.forename: Loïc
authors.initials: L
authors.lastname: Le Marchand
authors.forename: Laurence N
authors.initials: LN
authors.lastname: Kolonel
authors.forename: Marc T
authors.initials: MT
authors.lastname: Goodman
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000097:blood / Q000453:epidemiology / Q000208:ethnology* / Q000209:etiology*; D018567:Breast Neoplasms, Male / Q000097:blood / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology; D016022:Case-Control Studies; D015331:Cohort Studies; D018864:Cultural Diversity; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006254:Hawaii / Q000453:epidemiology; D006801:Humans; D015141:Los Angeles / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011153:Population; D017698:Postmenopause / Q000097:blood* / Q000502:physiology; D012307:Risk Factors
chemical_list: D012739:Gonadal Steroid Hormones