title: Urinary estrogen metabolites in women at high risk for breast cancer.
abstract: OBJECTIVE
  This study explored whether average urinary estrogen metabolites in breast cancer high-risk women can be used to identify a subgroup of women at particularly high risk to develop breast cancer, to which prevention strategies should be addressed.
  
  
  METHODS
  The population consisted of 77 high-risk women, 30 breast cancer patients and 41 controls. All subjects answered a standardized questionnaire; height and weight and spot urine samples were also obtained. Urine hydroxyestrogen metabolites were measured in triplicate by enzyme immunoassay, and the estrogen metabolite ratios for each individual were calculated.
  
  
  RESULTS
  The 2:16 OHE ratio (2-hydroxyestrone/16-alpha-hydroxyestrone) in women at high risk for breast cancer was similar to that observed in the breast cancer group (1.76 +/- 2.33 versus 1.29 +/- 0.80) and lower than in controls (2.47 +/- 1.14; P = 0.00). At the multivariate linear regression model, the 2:16 OHE ratio was significantly associated with diagnosis (P = 0.000 for both the high risk and breast cancer group versus the controls) and body mass index (P = 0.005), but not with age (P = 0.604), or smoking history (P = 0.478).
  
  
  CONCLUSIONS
  This study suggests that lower urinary 2:16 OHE ratios are predictors of breast cancer risk. Profiling estrogen metabolites may identify women who are more probably to develop breast cancer within a population of women with known risk factors and may help to further elucidate the clinical relevance of urinary 2:16 OHE ratios as clinical markers and prognostic indicators in this population.
authors.affiliation: Magee/UPCI Breast Cancer Prevention Program, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
authors.forename: Annie
authors.initials: A
authors.lastname: Im
authors.forename: Victor G
authors.initials: VG
authors.lastname: Vogel
authors.forename: Gretchen
authors.initials: G
authors.lastname: Ahrendt
authors.forename: Stacy
authors.initials: S
authors.lastname: Lloyd
authors.forename: Camille
authors.initials: C
authors.lastname: Ragin
authors.forename: Seymour
authors.initials: S
authors.lastname: Garte
authors.forename: Emanuela
authors.initials: E
authors.lastname: Taioli
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000652:urine; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000209:etiology / Q000235:genetics / Q000652:urine*; D005260:Female; D006801:Humans; D006894:Hydroxyestrones / Q000652:urine*; D016014:Linear Models; D008875:Middle Aged; D012907:Smoking / Q000652:urine
chemical_list: D006894:Hydroxyestrones; C026702:16-hydroxyestrone; C024980:2-hydroxyestrone