title: Prospective study of plasma enterolactone and prostate cancer risk (Sweden).
abstract: OBJECTIVE
  Enterolactone, a phytoestrogen produced by the intestinal microflora from precursors in plant foods, has been postulated to protect against hormone-dependent cancers. We studied the association between plasma enterolactone and risk of prostate cancer.
  
  
  METHODS
  In the Northern Sweden Health and Disease Cohort, enterolactone concentrations were measured by time-resolved fluoroimmunoassay in plasma taken from 265 men who were diagnosed with prostate cancer at a mean time of 5 years after blood collection, and in plasma from 525 control men, matched for age and date of blood collection.
  
  
  RESULTS
  There was no significant association between quartiles of plasma enterolactone and risk of prostate cancer. Odds ratios for prostate cancer, estimated by conditional logistic regression for increasing concentrations of enterolactone in quartiles were 1.00 (referent), 0.81 (95% confidence interval 0.52-1.27), 1.03 (0.67-1.58), and 1.22 (0.80-1.86). Adjustments for body mass index (BMI), smoking status and stratification for age, lag time, storage time and tumour characteristics did not materially alter risk estimates. Men with very low enterolactone levels, however, had significantly higher risk of prostate cancer, odds ratio for bottom decile versus all other deciles was 1.68 (1.03-2.74).
  
  
  CONCLUSIONS
  Our results do not support the hypothesis that enterolactone formed from dietary lignans protects against prostate cancer.
authors.affiliation: Department of Surgery and Perioperative Sciences, Urology and Andrology, Umed University Hospital, Sweden. par.stattin@urologi.umu.se
authors.forename: Pär
authors.initials: P
authors.lastname: Stattin
authors.forename: Annika
authors.initials: A
authors.lastname: Bylund
authors.forename: Carine
authors.initials: C
authors.lastname: Biessy
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kaaks
authors.forename: Göran
authors.initials: G
authors.lastname: Hallmans
authors.forename: Herman
authors.initials: H
authors.lastname: Adlercreutz
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000097:blood*; D015331:Cohort Studies; D006801:Humans; D008019:Life Style; D017705:Lignans / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D048789:Phytoestrogens / Q000097:blood*; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000097:blood / Q000453:epidemiology*; D012306:Risk; D012907:Smoking / Q000009:adverse effects; D013548:Sweden / Q000453:epidemiology
chemical_list: D017705:Lignans; D048789:Phytoestrogens; D015107:4-Butyrolactone; C029497:2,3-bis(3'-hydroxybenzyl)butyrolactone