title: Time to an undetectable prostate-specific antigen (PSA) after androgen suppression therapy for postoperative or postradiation PSA recurrence and prostate cancer-specific mortality.
abstract: BACKGROUND
  For men receiving androgen-suppression therapy (AST) for a rising postoperative or postradiation prostate-specific antigen (PSA) recurrence, whether the time to an undetectable (u) PSA was significantly associated with prostate cancer-specific mortality (PCSM) was evaluated.
  
  
  METHODS
  The study cohort comprised 585 men with a rising PSA and negative bone scan after surgery (n = 415) or radiation therapy (n = 170) that were treated with AST and achieved a uPSA. Gray's regression was used to evaluate whether the time to a uPSA after AST was significantly associated with the time to PCSM after the uPSA adjusting for known prognostic factors.
  
  
  RESULTS
  The median time (interquartile range) to achieve a uPSA was 4.6 (range, 2.8-7.8) months. There were 23 deaths, 4 of which were from prostate cancer. An increasing time to a uPSA (adjusted hazard ratio [HR]: 9.2, 95% confidence interval [CI]: 3.8, 22.1; P < .0001), a decreasing PSA doubling time (DT) (HR: 0.58, 95% CI: 0.43, 0.80; P = .0007), and Gleason score 8 to 10 cancers (HR: 8.6, 95% CI: 1.04, 77; P = .05) were significantly associated with a shorter time to PCSM.
  
  
  CONCLUSIONS
  Despite achieving a uPSA after AST, the risk of PCSM increased significantly as the time to the uPSA lengthens, especially in men with a short pre-AST PSA DT and high-grade prostate cancer. These men should be considered for randomized studies evaluating immediate vs delayed chemotherapy after the achievement of the uPSA.
authors.affiliation: Department of Radiation Oncology, Brigham and Women's Hospital and Dana Farber Cancer Institute, Boston, Massachusetts, USA. adamico@lroc.harvard.edu
authors.forename: Anthony V
authors.initials: AV
authors.lastname: D'Amico
authors.forename: David G
authors.initials: DG
authors.lastname: McLeod
authors.forename: Peter R
authors.initials: PR
authors.lastname: Carroll
authors.forename: Jennifer
authors.initials: J
authors.lastname: Cullen
authors.forename: Ming-Hui
authors.initials: MH
authors.lastname: Chen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000627:therapeutic use*; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000097:blood* / Q000401:mortality* / Q000628:therapy; D018570:Risk Assessment; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D018931:Antineoplastic Agents, Hormonal; D017430:Prostate-Specific Antigen