title: Effect of diindolylmethane supplementation on low-grade cervical cytological abnormalities: double-blind, randomised, controlled trial.
abstract: BACKGROUND
  Cervical screening identifies many women with low-grade abnormalities. In vitro and in vivo studies have shown that diindolylmethane (DIM) could potentially halt (cervical) carcinogenesis. We report on a randomised controlled trial of the effect of DIM in women with low-grade cervical cytological abnormalities.
  
  
  METHODS
  We conducted a pragmatic double-blind, randomised controlled trial of 150 mg DIM (from BioResponse DIM) or placebo daily for 6 months in women with newly diagnosed, low-grade cytological abnormalities. Randomisation was in the ratio 2 (DIM) to 1 (placebo). All women were invited for colposcopy at 6 months with biopsy of any abnormality.
  
  
  RESULTS
  Of the 551 randomised women available for analysis, 9% on DIM and 12% on placebo had cervical intraepithelial neoplasia-2 (CIN2) or worse after 6-month supplementation (risk ratio (RR) 0.7 (95% confidence interval (CI): 0.4-1.2)), whereas 4.6% and 5.1%, respectively, had CIN3 or worse (RR 0.9 (95% CI: 0.4-2.0)). A total of 27.3% of women on DIM and 34.3% on placebo had no sign of disease (negative cytology, colposcopy and human papilloma virus (HPV) tests) at 6 months (RR 0.8 (95% CI: 0.6-1.0)). Of those HPV-positive at baseline, 69% (114 out of 166) of the DIM group were positive at 6 months compared with 61% (43 out of 71) of the placebo group: RR 1.1 (95% CI: 0.9-1.4). Diindolylmethane supplementation was well tolerated.
  
  
  CONCLUSIONS
  The results suggest that short-term DIM supplementation (150 mg day(-1)) is well tolerated, but is unlikely to have an effect on cytology or HPV infection. Uncertainty remains regarding its effect on CIN2+.
authors.affiliation: Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
authors.forename: A
authors.initials: A
authors.lastname: Castañon
authors.forename: A
authors.initials: A
authors.lastname: Tristram
authors.forename: D
authors.initials: D
authors.lastname: Mesher
authors.forename: N
authors.initials: N
authors.lastname: Powell
authors.forename: H
authors.initials: H
authors.lastname: Beer
authors.forename: S
authors.initials: S
authors.lastname: Ashman
authors.forename: G
authors.initials: G
authors.lastname: Rieck
authors.forename: H
authors.initials: H
authors.lastname: Fielder
authors.forename: A
authors.initials: A
authors.lastname: Fiander
authors.forename: P
authors.initials: P
authors.lastname: Sasieni
mesh_terms: D000328:Adult; D052685:Alphapapillomavirus / Q000302:isolation & purification; D016588:Anticarcinogenic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007211:Indoles / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D008875:Middle Aged; D010919:Placebos; D002583:Uterine Cervical Neoplasms / Q000517:prevention & control; D002578:Uterine Cervical Dysplasia / Q000188:drug therapy* / Q000821:virology
chemical_list: D016588:Anticarcinogenic Agents; D007211:Indoles; D010919:Placebos; C016392:3,3'-diindolylmethane
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