title: Sexually transmissible infections and prostate cancer risk.
abstract: BACKGROUND
  Sexually transmissible infections (STI) have been variably associated with increased risks of prostate cancer, largely in case-control studies.
  
  
  METHODS
  In the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, we examined risk of prostate cancer in relation to serum antibodies to Chlamydia trachomatis, human papillomavirus-16 and -18, herpes simplex virus-2, cytomegalovirus, and human herpesvirus-8 in 868 cases (765 Whites and 103 Blacks) and 1,283 controls matched by race, age, time since initial screening, and year of blood draw; all blood samples were collected at least 1 year before prostate cancer diagnosis, except for 43 Black cases. We also assessed risk associated with self-reported history of syphilis and gonorrhea.
  
  
  RESULTS
  Prevalences of the 7 STIs among controls were weakly correlated, and all were more frequent among Blacks than Whites, except for human herpesvirus-8. Among Whites, prostate cancer risk was not significantly associated with the individual infections or with their number (P(trend) = 0.1); however, men with one or more STI had slightly higher risk (odds ratio, 1.3; 95% confidence interval, 1.0-1.6). Among Blacks, excess risk was associated with IgA antibody to C. trachomatis (odds ratio, 2.1; 95% confidence interval, 1.2-3.6).
  
  
  CONCLUSIONS
  This large prospective study of prostate cancer shows no consistent association with specific STIs and a borderline association with any versus none. Whether a shared response or correlated infection not directly measured underlies the weak association requires further study.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Bethesda, MD 20892, USA. huangw@mail.nih.gov
authors.forename: Wen-Yi
authors.initials: WY
authors.lastname: Huang
authors.forename: Richard
authors.initials: R
authors.lastname: Hayes
authors.forename: Ruth
authors.initials: R
authors.lastname: Pfeiffer
authors.forename: Raphael P
authors.initials: RP
authors.lastname: Viscidi
authors.forename: Francis K
authors.initials: FK
authors.lastname: Lee
authors.forename: Yun F
authors.initials: YF
authors.lastname: Wang
authors.forename: Douglas
authors.initials: D
authors.lastname: Reding
authors.forename: Denise
authors.initials: D
authors.lastname: Whitby
authors.forename: John R
authors.initials: JR
authors.lastname: Papp
authors.forename: Charles S
authors.initials: CS
authors.lastname: Rabkin