title: High-risk Prostate Cancer Treated With Dose-escalated RT: An Analysis of Hormonal Therapy Use and Duration, and Prognostic Implications of PSA Nadir ≤0.2 to Select Men for Short-term Hormonal Therapy.
abstract: OBJECTIVE
  To determine prognostic factors to select high-risk men receiving dose-escalated radiation therapy (RT) who will have favorable outcomes with short-term (ST) or no androgen deprivation therapy (ADT).
  
  
  METHODS
  Medical records of 458 men treated with definitive RT for high-risk, nonmetastatic prostate cancer at 3 academic referral centers from 1988 to 2009 were examined. Median dose was 76.4 Gy. Men received no ADT (n=105), STADT (<12 mo, n=194), or long-term ADT (LTADT: ≥12 mo, n=160). Univariate and multivariable analysis for freedom from distant metastases (FFDM) and cause-specific survival (CSS) were performed. Median follow-up was 71 months.
  
  
  RESULTS
  Seven-year FFDM was 83% and CSS was 91%. Multivariable analysis demonstrated that prostate-specific antigen (PSA) nadir ≤0.2 (HR=0.36; 95% CI, 0.20-0.64) and Gleason score (GS) were associated with FFDM and CSS (all P<0.05). ADT duration was not associated (P>0.05). Those with PSA nadir ≤0.2 ng/mL had improved outcomes. Men with GS 9 disease did poorly despite a PSA nadir ≤0.2 ng/mL and had improved CSS with LTADT (95% vs. 71%, P<0.05).
  
  
  CONCLUSIONS
  Select men with high-risk disease treated with dose-escalated RT may not require LTADT. In men treated with ADT, PSA nadir ≤0.2 is an independent prognostic factor associated with FFDM and CSS. Men without GS 9 may have acceptable outcomes with STADT if PSA nadir is ≤0.2 ng/mL. Further investigation is necessary to elucidate the role of PSA nadir in determining the optimal length of adjuvant ADT.
authors.affiliation: *Department of Radiation and Cellular Oncology, The University of Chicago Medicine, Chicago, IL †Department of Radiation Oncology, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Christina H
authors.initials: CH
authors.lastname: Son
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Hamstra
authors.forename: Felix Y
authors.initials: FY
authors.lastname: Feng
authors.forename: Stanley L
authors.initials: SL
authors.lastname: Liauw
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D000970:Antineoplastic Agents; D017430:Prostate-Specific Antigen