title: Efficacy of intermittent androgen deprivation therapy vs conventional continuous androgen deprivation therapy for advanced prostate cancer: a meta-analysis.
abstract: OBJECTIVE
  To compare the efficacy of intermittent androgen deprivation therapy (IADT) vs continuous androgen deprivation therapy (CADT) for the treatment of advanced prostate cancer; we performed a meta-analysis of randomized controlled trials (RCTs), assessing the risks of disease progression, all-cause, and disease-specific mortality.
  
  
  METHODS
  We conducted a systematic search of several bibliographic systems to identify all RCTs of IADT in men with newly diagnosed metastatic or biochemical only prostate cancer. We abstracted outcome data, study characteristics, and participant demographics. We performed heterogeneity tests and calculated the summarized risk differences (RD) and risk ratios at 95% confidence intervals (CI), using inverse variance methods in random-effects approaches.
  
  
  RESULTS
  We identified 8 RCTs (N = 4664) comparing mortality between IADT and CADT. For all men combined, we observed small but nonsignificant differences in all-cause mortality (RD = 0.02, 95% CI = -0.02, 0.06), disease-specific mortality (RD = 0.04, 95% CI = -0.01, 0.08), and disease progression (RD = -0.03, 95% CI = -0.09, 0.04). Among the prespecified subgroup with histologically confirmed, newly diagnosed metastatic disease, we found no difference in overall survival (RD = 0.00, 95% CI = -0.09, 0.09).
  
  
  CONCLUSIONS
  We found no difference in overall survival, but a small increased risk in disease-specific survival for men treated with IADT relative to CADT was observed. IADT could be considered as an alternative to CADT because of better quality of life outcome. Patients should be informed of the possible risks and benefits of both therapies. More research confirming the benefits of IADT vs CADT is needed to inform treatment decisions.
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA. ccsuny.tw@gmail.com
authors.forename: Huei-Ting
authors.initials: HT
authors.lastname: Tsai
authors.forename: David F
authors.initials: DF
authors.lastname: Penson
authors.forename: Kepher H
authors.initials: KH
authors.lastname: Makambi
authors.forename: John H
authors.initials: JH
authors.lastname: Lynch
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Van Den Eeden
authors.forename: Arnold L
authors.initials: AL
authors.lastname: Potosky
mesh_terms: D000726:Androgen Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D016001:Confidence Intervals; D018450:Disease Progression; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists* / Q000037:antagonists & inhibitors*; D006801:Humans; D008297:Male; D016017:Odds Ratio; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D016032:Randomized Controlled Trials as Topic; D016019:Survival Analysis
chemical_list: D000726:Androgen Antagonists; D007987:Gonadotropin-Releasing Hormone
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