title: Role of androgen deprivation therapy in early salvage radiation among patients with prostate-specific antigen level of 0.5 or less.
abstract: BACKGROUND
  The Radiation Therapy Oncology Group 96-01 randomized trial demonstrated the benefit of adding androgen deprivation therapy (ADT) to salvage radiotherapy for an increasing prostate-specific antigen (PSA) after prostatectomy, but it is unknown whether modern patients followed with ultrasensitive PSA and salvaged at a low PSA (ie, ≤ 0.5) also benefit from ADT.
  
  
  METHODS
  The cohort comprised 108 patients who received radical prostatectomy (RP), were followed by ultrasensitive PSA, and received salvage radiotherapy at a PSA of 0.5 or less. Sixty patients had negative margins, and 48 patients had positive margins at RP. Cox multivariable regression analysis was performed to identify factors associated with time to secondary PSA failure and included PSA at salvage, year of treatment, Gleason score, ADT use, margin status, T stage, and PSA doubling time. Occurrence of distant metastases was documented.
  
  
  RESULTS
  Median follow-up after radiation was 63.09 months. A total of 24 patients had a distant metastasis. In all patients, ADT use was associated with a decreased risk of recurrence (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.25-0.79; P = .006). On subgroup analysis, ADT was associated with a decreased risk of failure among patients with negative margins (HR, 0.27; 95% CI, 0.12-0.61; P = .002), but not among men with positive margins (HR, 0.78; 95% CI, 0.29-2.10; P = .63).
  
  
  CONCLUSIONS
  Even patients followed with ultrasensitive PSA and salvaged early with a PSA ≤ 0.5 seem to benefit from the addition of ADT to salvage radiation. However, this benefit seemed to be limited to men with negative margins; thus, men with positive margins and PSA ≤ 0.5 may be good candidates for salvage radiation alone.
authors.affiliation: Department of Radiation Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Arti
authors.initials: A
authors.lastname: Parekh
authors.affiliation: Department of Statistics, University of Connecticut, Storrs, CT.
authors.forename: Ming-Hui
authors.initials: MH
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Powell
authors.initials: P
authors.lastname: Graham
authors.affiliation: Department of Radiation Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Brandon A
authors.initials: BA
authors.lastname: Mahal
authors.affiliation: Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA.
authors.forename: Ariel E
authors.initials: AE
authors.lastname: Hirsch
authors.affiliation: Department of Medical Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Mari
authors.initials: M
authors.lastname: Nakabayashi
authors.affiliation: Department of Medical Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Evan
authors.affiliation: Department of Medical Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Philip W
authors.initials: PW
authors.lastname: Kantoff
authors.affiliation: Department of Radiation Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Neil E
authors.initials: NE
authors.lastname: Martin
authors.affiliation: Department of Radiation Oncology, Dana Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA. Electronic address: pnguyen@LROC.harvard.edu.
authors.forename: Paul L
authors.initials: PL
authors.lastname: Nguyen
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use; D000813:Anilides / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy*; D009570:Nitriles / Q000627:therapeutic use*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000532:radiotherapy; D016032:Randomized Controlled Trials as Topic; D016879:Salvage Therapy; D014105:Tosyl Compounds / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D000813:Anilides; D000970:Antineoplastic Agents; D009570:Nitriles; D014105:Tosyl Compounds; D007987:Gonadotropin-Releasing Hormone; C053541:bicalutamide; D017430:Prostate-Specific Antigen
keywords: ADT; Prostate cancer; Salvage therapy; Surgical margins; Ultrasensitive PSA