title: Predictors for response to intermittent androgen deprivation (IAD) in prostate cancer cases with biochemical progression after surgery.
abstract: OBJECTIVE
  To define characteristics of the first cycle of intermittent androgen deprivation (IAD) that would predict for outcomes in a long term follow-up.
  
  
  METHODS
  In 1996 we started a prospective study of IAD for the treatment of biochemical progression (BP) after radical prostatectomy (RP) for prostate cancer (PC). The end-points of the trial were time to clinical progression (CP) and time to castration resistance PC (CRPC). Eighty-four cases were included in the study. In all cases, after an initial induction period, an acceptable nadir to switch from on-to-off-phase of IAD was considered to be a serum PSA < 1.0 ng/ml.
  
  
  METHODS
  As possible predictors for time to CP and CRPC, we analyzed pretreatment parameters such as age, Gleason Score, serum PSA, testosterone, chromogranina A (CgA) levels, and characteristics from the first cycle of IAD.
  
  
  RESULTS
  Mean follow-up during IAD was 88.6 ± 16.7 months; 29.7% of patients developed CRPC and 14.2% of cases showed a CP with a mean time of 88.4 ± 14.3 months and 106.5 ± 20.6 months, respectively. At univariate and multivariate analysis, the PSA nadir during the first on-phase period and the first off-phase interval resulted in significant and independent predictors (P < 0.001) of the time to CRPC and CP. In particular for cases with a PSA nadir > 0.4 ng/ml and for those with an off-phase interval ≤ 24 weeks, the risk of CRPC and CP during IAD was 2.7-2.5 and 3.0-3.1 times that for patients with a PSA nadir ≤ 0.1 ng/ml and with an off-phase interval > 48 weeks, respectively.
  
  
  CONCLUSIONS
  Cases with BP after RP selected to IAD that show at the first cycle a PSA nadir ≤ 0.1 ng/ml and a off-phase interval ≥ 48 weeks may identify candidates who will experience better response to IAD treatments and delayed CP or CRPC development.
authors.affiliation: Department of Urology, University Sapienza, Rome, Italy. sciarra.md@libero.it
authors.forename: Alessandro
authors.initials: A
authors.lastname: Sciarra
authors.forename: Susanna
authors.initials: S
authors.lastname: Cattarino
authors.forename: Alessandro
authors.initials: A
authors.lastname: Gentilucci
authors.forename: Andrea
authors.initials: A
authors.lastname: Alfarone
authors.forename: Michele
authors.initials: M
authors.lastname: Innocenzi
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Gentile
authors.forename: Stefano
authors.initials: S
authors.lastname: Salciccia
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D053379:Chromogranin A / Q000097:blood; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000601:surgery*; D064129:Prostatic Neoplasms, Castration-Resistant; D013739:Testosterone / Q000097:blood; D013997:Time Factors
chemical_list: D000726:Androgen Antagonists; D053379:Chromogranin A; D013739:Testosterone; D017430:Prostate-Specific Antigen