title: The impact of timing of salvage hormonal therapy on survival after brachytherapy for prostate cancer.
abstract: We aimed to evaluate the impact of timing of androgen deprivation therapy (ADT) on survival in a cohort of patients with biochemical recurrence (BCR) after brachytherapy treatment for prostate cancer.
  
  
  
  We retrospectively identified 2366 men receiving permanent prostate brachytherapy with or without external beam radiation therapy. Patients experiencing BCR were stratified by receipt of immediate or delayed (≥3 months) ADT and prostate-specific antigen (PSA) failure threshold of 10 ng/mL. Prostate cancer-specific mortality (PCSM) and all-cause mortality (ACM) were evaluated using Fine-Gray's competing risks regression and Cox proportional hazard model, respectively.
  
  
  
  We identified 109 patients in the study cohort treated with ADT for BCR, followed for a median of 11.4 years. Competing risk regression revealed that there was no difference in PCSM for patients receiving delayed vs. immediate ADT (hazard ratio [HR], 0.94; 95% confidence interval [CI]: 0.44-2.00: p = 0.871) or for those initiating hormonal therapy at PSA threshold of 10 vs. <10 ng/mL (HR, 0.85; 95% CI: 0.41-1.75; p = 0.649); similarly, there was no difference in ACM. PSA doubling time <6 months (HR, 2.52; 95% CI: 1.22-5.23; p = 0.013), time to BCR <3 years (HR, 3.27; 95% CI: 1.67-6.42; p = 0.003), and permanent prostate brachytherapy with external beam radiation therapy (HR, 5.21; 95% CI: 2.05-13.26; p = 0.001) were significantly associated with PCSM, as well as ACM.
  
  
  
  Among a cohort of brachytherapy patients, we identified no significant difference in survival for delayed salvage hormonal therapy. Shorter PSA doubling time and time to BCR are significantly associated with adverse outcomes, and these patients should be considered for immediate salvage therapy.
authors.affiliation: Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY. Electronic address: dsag127@gmail.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Sagalovich
authors.affiliation: Department of Urology, Yale University School of Medicine, New Haven, CT.
authors.forename: Michael
authors.initials: M
authors.lastname: Leapman
authors.affiliation: Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: John
authors.initials: J
authors.lastname: Sfakianos
authors.affiliation: Department of Urology, Long Island Jewish Medical Center, New Hyde Park, NY.
authors.forename: Simon
authors.initials: S
authors.lastname: Hall
authors.affiliation: Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Richard
authors.initials: R
authors.lastname: Stock
authors.affiliation: Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Nelson
authors.initials: N
authors.lastname: Stone
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001918:Brachytherapy / Q000379:methods*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000532:radiotherapy*; D012044:Regression Analysis; D012189:Retrospective Studies; D016879:Salvage Therapy / Q000379:methods*; D061665:Time-to-Treatment
chemical_list: D000726:Androgen Antagonists; D000970:Antineoplastic Agents; D017430:Prostate-Specific Antigen
keywords: Androgen deprivation; Brachytherapy; Prostate cancer; Salvage treatment; Survival