title: Effect of selenium and vitamin E on risk of prostate cancer and other cancers: the Selenium and Vitamin E Cancer Prevention Trial (SELECT).
abstract: BACKGROUND
  Secondary analyses of 2 randomized controlled trials and supportive epidemiologic and preclinical data indicated the potential of selenium and vitamin E for preventing prostate cancer.
  
  
  OBJECTIVE
  To determine whether selenium, vitamin E, or both could prevent prostate cancer and other diseases with little or no toxicity in relatively healthy men.
  
  
  METHODS
  A randomized, placebo-controlled trial (Selenium and Vitamin E Cancer Prevention Trial [SELECT]) of 35,533 men from 427 participating sites in the United States, Canada, and Puerto Rico randomly assigned to 4 groups (selenium, vitamin E, selenium + vitamin E, and placebo) in a double-blind fashion between August 22, 2001, and June 24, 2004. Baseline eligibility included age 50 years or older (African American men) or 55 years or older (all other men), a serum prostate-specific antigen level of 4 ng/mL or less, and a digital rectal examination not suspicious for prostate cancer.
  
  
  METHODS
  Oral selenium (200 microg/d from L-selenomethionine) and matched vitamin E placebo, vitamin E (400 IU/d of all rac-alpha-tocopheryl acetate) and matched selenium placebo, selenium + vitamin E, or placebo + placebo for a planned follow-up of minimum of 7 years and a maximum of 12 years.
  
  
  METHODS
  Prostate cancer and prespecified secondary outcomes, including lung, colorectal, and overall primary cancer.
  
  
  RESULTS
  As of October 23, 2008, median overall follow-up was 5.46 years (range, 4.17-7.33 years). Hazard ratios (99% confidence intervals [CIs]) for prostate cancer were 1.13 (99% CI, 0.95-1.35; n = 473) for vitamin E, 1.04 (99% CI, 0.87-1.24; n = 432) for selenium, and 1.05 (99% CI, 0.88-1.25; n = 437) for selenium + vitamin E vs 1.00 (n = 416) for placebo. There were no significant differences (all P>.15) in any other prespecified cancer end points. There were statistically nonsignificant increased risks of prostate cancer in the vitamin E group (P = .06) and type 2 diabetes mellitus in the selenium group (relative risk, 1.07; 99% CI, 0.94-1.22; P = .16) but not in the selenium + vitamin E group.
  
  
  CONCLUSIONS
  Selenium or vitamin E, alone or in combination at the doses and formulations used, did not prevent prostate cancer in this population of relatively healthy men.
  
  
  BACKGROUND
  clinicaltrials.gov identifier: NCT00006392.
authors.affiliation: Division of Cancer Medicine, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA. slippman@mdanderson.org
authors.forename: Scott M
authors.initials: SM
authors.lastname: Lippman
authors.forename: Eric A
authors.initials: EA
authors.lastname: Klein
authors.forename: Phyllis J
authors.initials: PJ
authors.lastname: Goodman
authors.forename: M Scott
authors.initials: MS
authors.lastname: Lucia
authors.forename: Ian M
authors.initials: IM
authors.lastname: Thompson
authors.forename: Leslie G
authors.initials: LG
authors.lastname: Ford
authors.forename: Howard L
authors.initials: HL
authors.lastname: Parnes
authors.forename: Lori M
authors.initials: LM
authors.lastname: Minasian
authors.forename: J Michael
authors.initials: JM
authors.lastname: Gaziano
authors.forename: Jo Ann
authors.initials: JA
authors.lastname: Hartline
authors.forename: J Kellogg
authors.initials: JK
authors.lastname: Parsons
authors.forename: James D
authors.initials: JD
authors.lastname: Bearden
authors.forename: E David
authors.initials: ED
authors.lastname: Crawford
authors.forename: Gary E
authors.initials: GE
authors.lastname: Goodman
authors.forename: Jaime
authors.initials: J
authors.lastname: Claudio
authors.forename: Eric
authors.initials: E
authors.lastname: Winquist
authors.forename: Elise D
authors.initials: ED
authors.lastname: Cook
authors.forename: Daniel D
authors.initials: DD
authors.lastname: Karp
authors.forename: Philip
authors.initials: P
authors.lastname: Walther
authors.forename: Michael M
authors.initials: MM
authors.lastname: Lieber
authors.forename: Alan R
authors.initials: AR
authors.lastname: Kristal
authors.forename: Amy K
authors.initials: AK
authors.lastname: Darke
authors.forename: Kathryn B
authors.initials: KB
authors.lastname: Arnold
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Ganz
authors.forename: Regina M
authors.initials: RM
authors.lastname: Santella
authors.forename: Demetrius
authors.initials: D
authors.lastname: Albanes
authors.forename: Philip R
authors.initials: PR
authors.lastname: Taylor
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Probstfield
authors.forename: T J
authors.initials: TJ
authors.lastname: Jagpal
authors.forename: John J
authors.initials: JJ
authors.lastname: Crowley
authors.forename: Frank L
authors.initials: FL
authors.lastname: Meyskens
authors.forename: Laurence H
authors.initials: LH
authors.lastname: Baker
authors.forename: Charles A
authors.initials: CA
authors.lastname: Coltman
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000627:therapeutic use*; D019587:Dietary Supplements; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology / Q000517:prevention & control; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D012643:Selenium / Q000627:therapeutic use*; D012645:Selenomethionine / Q000627:therapeutic use; D016896:Treatment Outcome; D014810:Vitamin E / Q000627:therapeutic use*; D024502:alpha-Tocopherol / Q000627:therapeutic use
chemical_list: D000975:Antioxidants; D014810:Vitamin E; D012645:Selenomethionine; D024502:alpha-Tocopherol; D012643:Selenium