title: Prostate cancer-specific mortality after definitive radiation therapy: who dies of disease?
abstract: BACKGROUND
  A competing risks analysis was undertaken to identify subgroups at greatest risk of dying from prostate cancer (PC) after definitive external beam radiation therapy (RT)±androgen deprivation therapy (ADT) in the prostate specific antigen (PSA) era.
  
  
  METHODS
  Outcomes of 2675 men with localised PC treated with RT±ADT from 1987-2007 were analysed. Prostate cancer-specific mortality (PCSM) and non-PCSM rates were calculated after stratifying patients according to National Comprehensive Cancer Network (NCCN) risk-group, RT dose, use of ADT and age at treatment.
  
  
  RESULTS
  Only 0.2% of low-risk men died of PC 10 years after treatment. All of these deaths occurred in patients treated with < 72 Gy, and only one patient ≥ 70 years old who received ≥ 72 Gy died of PC at last follow-up. Likewise, none of the patients with intermediate-risk disease treated with ≥ 72 Gy and ADT died of PC at 10 years, and the highest 10-year rate of PCSM was seen in men ≥ 70 years old treated with < 72 Gy without ADT (5.1%). Among high-risk men < 70 years old, treatment with RT dose < 72 Gy without ADT yielded similar 10-year rates of PCSM (15.2%) and non-PCSM (18.5%), whereas men treated with ≥ 72 Gy and ADT were twice as likely to die from other causes (16.2%) than PC (9.4%). In high-risk men ≥ 70 years old, dose-escalation with ADT reduced 10-year PCSM from 14% to 4%, and most deaths were due to other causes.
  
  
  CONCLUSIONS
  Low- and intermediate-risk patients treated with definitive RT are unlikely to die of PC. PCSM is higher in men with high-risk disease but may be reduced with dose-escalation and ADT, although patients are still twice as likely to die of other causes.
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard Unit 97, Houston, TX 77030-4009, USA. mmkim@mdanderson.org
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Kim
authors.forename: Karen E
authors.initials: KE
authors.lastname: Hoffman
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Levy
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Frank
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Pugh
authors.forename: Seungtaek
authors.initials: S
authors.lastname: Choi
authors.forename: Quynh N
authors.initials: QN
authors.lastname: Nguyen
authors.forename: Sean E
authors.initials: SE
authors.lastname: McGuire
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Lee
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Kuban
mesh_terms: D000367:Age Factors; D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use; D002423:Cause of Death; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000401:mortality* / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D018570:Risk Assessment; D015996:Survival Rate; D014481:United States
chemical_list: D000726:Androgen Antagonists