title: Update on prostate cancer chemoprevention.
abstract: BACKGROUND
  Prostate cancer is the most common type of cancer and the second leading cause of cancer-related deaths in American men. Its high rate of occurrence and long lead time to clinically significant disease make prostate cancer an ideal disease for pharmacologic or nutritional chemoprevention.
  
  
  METHODS
  To identify the various chemoprevention strategies for prostate cancer, a MEDLINE search (from 1967-2005) and bibliographic search of the English-language literature were conducted.
  
  
  RESULTS
  Epidemiologic and retrospective studies have assessed the effect of carotenoids (e.g., lycopene), vitamins, selenium, and nonsteroidal antiinflammatory drugs (NSAIDs) on the rate of occurrence of prostate cancer. The few published prospective trials evaluated prostate cancer as a secondary end point. Lycopene (as beta-carotene) and selenium supplementation have been associated with a reduced risk of prostate cancer in nested case-control studies, but only in subgroups of men with low baseline plasma lycopene (or beta-carotene) and selenium levels respectively. The Prostate Cancer Prevention Trial prospectively evaluated finasteride, a 5-alpha-reductase inhibitor, as chemoprevention. The results showed a 25% relative risk reduction in prostate cancer, albeit at an increased risk of invasive tumors.
  
  
  CONCLUSIONS
  Data regarding lycopene, vitamin E, and selenium as chemoprevention for prostate cancer appear promising. Prospective trials such as the Selenium and Vitamin E Cancer Prevention Trial (SELECT) will clarify the role of these agents in prostate cancer prevention. The role of NSAIDs is unclear, and the long-term toxicity associated with NSAIDs may limit their usefulness. Although finasteride has decreased overall prostate cancer occurrence, the risk of invasive tumors may outweigh the benefit of this agent. The continuing Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial may help define a role for the 5-alpha-reductase inhibitors in cancer chemoprevention. At this time, nothing has been proven effective as chemoprevention against clinically significant prostate cancer.
authors.affiliation: Department of Pharmacy, Akron General Medical Center, Akron, Ohio 44307, USA. jfisher1@agmc.org
authors.forename: Jennifer Fisher
authors.initials: JF
authors.lastname: Lowe
authors.forename: Lawrence A
authors.initials: LA
authors.lastname: Frazee
mesh_terms: D058891:5-alpha Reductase Inhibitors; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D001378:Azasteroids / Q000627:therapeutic use; D002338:Carotenoids / Q000627:therapeutic use; D018890:Chemoprevention; D002986:Clinical Trials as Topic; D000068538:Dutasteride; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D018120:Finasteride / Q000627:therapeutic use; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000517:prevention & control*; D012643:Selenium / Q000627:therapeutic use; D014810:Vitamin E / Q000627:therapeutic use; D014815:Vitamins / Q000627:therapeutic use
chemical_list: D058891:5-alpha Reductase Inhibitors; D000894:Anti-Inflammatory Agents, Non-Steroidal; D001378:Azasteroids; D004791:Enzyme Inhibitors; D014815:Vitamins; D014810:Vitamin E; D002338:Carotenoids; D018120:Finasteride; D012643:Selenium; D000068538:Dutasteride