title: International study into the use of intermittent hormone therapy in the treatment of carcinoma of the prostate: a meta-analysis of 1446 patients.
abstract: OBJECTIVE
  To review pooled phase II data to identify features of different regimens of intermittent hormone therapy (IHT), developed to reduce the morbidity of treating metastatic prostate cancer, and which carries a theoretical advantage of delaying the onset of androgen-independent prostate cancer, (AIPC) that are associated with success, highlighting features which require exploration with prospective trials to establish the best strategies for using this treatment.
  
  
  METHODS
  Individual data were collated on 1446 patients with adequate information, from 10 phase II studies with >50 cases, identified through Pubmed.
  
  
  RESULTS
  Univariate and multivariate Cox proportional hazard models were developed to predict treatment success with a high degree of statistical success. The prostate-specific antigen (PSA) nadir, the PSA threshold to restart treatment, and medication type and duration, were important predictors of outcome.
  
  
  CONCLUSIONS
  The duration of biochemical remission after a period of HT is a durable early indicator of how rapidly AIPC and death will occur, and will make a useful endpoint in future trials to investigate the best ways to use IHT based on the important treatment cycling variables described above. Patients spent a mean of 39% of the time off treatment. The initial PSA level and PSA nadir allow the identification of patients with prostate cancer in whom it might be possible to avoid radical therapy.
authors.affiliation: St Bartholemew's Hospital, London, UK, and University of Western Australia, Perth, Australia. gregshaw@doctors.org.uk
authors.forename: Greg L
authors.initials: GL
authors.lastname: Shaw
authors.forename: Peter
authors.initials: P
authors.lastname: Wilson
authors.forename: Jack
authors.initials: J
authors.lastname: Cuzick
authors.forename: David M
authors.initials: DM
authors.lastname: Prowse
authors.forename: S Larry
authors.initials: SL
authors.lastname: Goldenberg
authors.forename: Nigel A
authors.initials: NA
authors.lastname: Spry
authors.forename: Tim
authors.initials: T
authors.lastname: Oliver
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D000728:Androgens / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017322:Clinical Trials, Phase II as Topic; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D000728:Androgens; D000970:Antineoplastic Agents; D017430:Prostate-Specific Antigen