title: Prognostic model of event-free survival for patients with androgen-independent prostate carcinoma.
abstract: BACKGROUND
  The current study was conducted to develop a prognostic model of event-free survival (EFS) in men with androgen-independent prostate carcinoma (AIPC).
  
  
  METHODS
  Data from 160 patients diagnosed with AIPC between 1989-2002 were reviewed. No patient had received cytotoxic chemotherapy. A univariate Cox proportional hazards model identified significant predictors of EFS. Recursive partitioning analysis divided these significant variables into prognostic risk groups. The final prognostic model was tested with a Cox proportional hazards model.
  
  
  RESULTS
  The final prognostic risk model included the presence of metastatic disease at the time of androgen-independent disease progression (P = 0.040), time to prostate-specific antigen (PSA) recurrence (P = 0.043), and PSA doubling time (P < 0.01). Three highly independent risk groups were identified. The observed median EFSs were 6.1 months (95% confidence interval [95= CI], 3.4-8.8 months), 33.6 months (95= CI, 25.3-41.9 months), and 96.1 months (95= CI, 57.9-134.3 months) for the low-risk, intermediate-risk, and high-risk groups, respectively. Each risk group was found to be independently predictive of EFS (P < 0.01). Patients who died of prostate carcinoma experienced significantly more clinical events than those who died of other causes (P < 0.01).
  
  
  CONCLUSIONS
  The prognostic model in the current study stratified patients into three highly significant and independent risk groups for EFS. A detailed PSA history and knowledge of metastatic disease are sufficient to risk-stratify patients with AIPC. One very unique aspect of this model was that it was developed from a patient cohort that never received chemotherapy.
authors.affiliation: Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Shulman
authors.forename: Elie A
authors.initials: EA
authors.lastname: Benaim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000728:Androgens / Q000627:therapeutic use; D015331:Cohort Studies; D018450:Disease Progression; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009367:Neoplasm Staging; D009376:Neoplasms, Hormone-Dependent / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D000728:Androgens; D017430:Prostate-Specific Antigen