title: Long-term Exposure to Testosterone Therapy and the Risk of High Grade Prostate Cancer.
abstract: OBJECTIVE
  To our knowledge no population based studies have been done to examine whether long-term exposure to testosterone therapy is associated with an increased risk of high grade prostate cancer. We examined whether exposure to testosterone during a 5-year period was associated with an increased risk of high grade prostate cancer and whether this risk increased in a dose-response fashion with the cumulative number of testosterone injections.
  
  
  METHODS
  Using SEER (Surveillance, Epidemiology and End Results)-Medicare linked data we identified 52,579 men diagnosed with incident prostate cancer between January 1, 2001 and December 31, 2006 who had a minimum of 5 years continuous enrollment in Medicare before the cancer diagnosis. We excluded patients diagnosed at death or after autopsy, those enrolled in a health maintenance organization in the 60 months before diagnosis and those with unknown tumor grade or tumor stage. In the 5 years before diagnosis 574 men had a history of testosterone use and 51,945 did not.
  
  
  RESULTS
  On logistic regression adjusting for demographic and clinical characteristics exposure to testosterone therapy was not associated with an increased risk of high grade prostate cancer (OR 0.84, 95% CI 0.67-1.05) or receipt of primary androgen deprivation therapy following diagnosis (OR 0.97, 95% CI 0.74-1.30). In addition the risk of high grade disease did not increase according to the total number of testosterone injections (OR 1.00, 95% CI 0.98-1.01).
  
  
  CONCLUSIONS
  Our finding that testosterone therapy was not associated with an increased risk of high grade prostate cancer may provide important information regarding the risk-benefit assessment for men with testosterone deficiency considering treatment.
authors.affiliation: Department of Internal Medicine, Sealy Center on Aging, University of Texas Medical Branch, Galveston, Texas. Electronic address: jbaillar@utmb.edu.
authors.forename: Jacques
authors.initials: J
authors.lastname: Baillargeon
authors.affiliation: Department of Internal Medicine, Sealy Center on Aging, University of Texas Medical Branch, Galveston, Texas.
authors.forename: Yong-Fang
authors.initials: YF
authors.lastname: Kuo
authors.affiliation: Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, Texas.
authors.forename: Xiao
authors.initials: X
authors.lastname: Fang
authors.affiliation: Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan.
authors.forename: Vahakn B
authors.initials: VB
authors.lastname: Shahinian
mesh_terms: D000368:Aged; D004305:Dose-Response Relationship, Drug; D020249:Hormone Replacement Therapy / Q000009:adverse effects*; D006801:Humans; D016015:Logistic Models; D008134:Long-Term Care; D008297:Male; D060787:Neoplasm Grading; D011471:Prostatic Neoplasms / Q000139:chemically induced* / Q000473:pathology*; D018570:Risk Assessment; D018426:SEER Program; D013739:Testosterone / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D014481:United States
chemical_list: D013739:Testosterone; C016131:testosterone 17 beta-cypionate
keywords: SEER program; androgens; neoplasm grade; prostatic neoplasms; testosterone