title: Androgens and prostate cancer risk: a prospective study.
abstract: BACKGROUND
  Androgens have been implicated in prostate tumorigenesis, but prospective studies have overall reported no association between circulating levels of androgens and risk of prostate cancer. However, some recent studies have shown that a high level of testosterone increase the risk of non-aggressive tumors but is associated with a decreased risk of aggressive tumors.
  
  
  METHODS
  We prospectively measured plasma levels of total testosterone, androstanediol glucuronide (A-diol-g) and sex hormone binding globuline (SHBG) and calculated estimated levels of free testosterone, in a nested case-control study of 392 cases and 392 matched controls.
  
  
  RESULTS
  None of the studied hormones were significantly associated with prostate cancer risk in the full study group or in subgroups according to tumor aggressiveness. Odds ratios in the full study group, for top versus bottom quartile, was for total testosterone 1.25 (95% CI = 0.79-2.00; P(trend) = 0.51); free testosterone, 1.31 (95% CI = 0.82-2.07; P(trend) = 0.35); A-diol-g, 0.88 (95% CI = 0.59-1.33; P(trend) = 0.77); and for SHBG, 1.01 (95% CI = 0.64-1.58; P(trend) = 0.94).
  
  
  CONCLUSIONS
  We found no significant associations between androgen levels and risk of prostate cancer in this population-based, non-screened cohort.
authors.affiliation: Department of Surgical and Perioperative Sciences, Urology and Andrology, Umeå University, Umeå, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Wirén
authors.forename: Tanja
authors.initials: T
authors.lastname: Stocks
authors.forename: Sabina
authors.initials: S
authors.lastname: Rinaldi
authors.forename: Göran
authors.initials: G
authors.lastname: Hallmans
authors.forename: Anders
authors.initials: A
authors.lastname: Bergh
authors.forename: Ulf-Håkan
authors.initials: UH
authors.lastname: Stenman
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kaaks
authors.forename: Pär
authors.initials: P
authors.lastname: Stattin
mesh_terms: D000728:Androgens / Q000097:blood*; D015113:Androstane-3,17-diol / Q000031:analogs & derivatives / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology; D012307:Risk Factors; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013739:Testosterone / Q000097:blood
chemical_list: D000728:Androgens; D012738:Sex Hormone-Binding Globulin; D015113:Androstane-3,17-diol; C028895:androstane-3,17-diol glucuronide; D013739:Testosterone