title: Survival Outcomes of Dose-Escalated External Beam Radiotherapy versus Combined Brachytherapy for Intermediate and High Risk Prostate Cancer Using the National Cancer Data Base.
abstract: OBJECTIVE
  We evaluated survival outcomes between dose-escalated EBRT (external beam radiotherapy) vs EBRT plus brachytherapy for intermediate and high risk prostate cancer using NCDB (National Cancer Data Base).
  
  
  METHODS
  Patients with cN0M0 prostate cancer treated from 2004 to 2006 were divided into radiotherapy comparison groups, including EBRT alone (75.6 to 81 Gy) and EBRT (40 to 50.4 Gy) plus brachytherapy with EBRT delivered at 1.8 to 2.0 Gy per fraction. Brachytherapy data were limited to yes/no with no information on modality, dose or schedule. Eligible patients were known to have received androgen deprivation therapy. Overall survival was evaluated using multivariate Cox regression and propensity score matched analyses.
  
  
  RESULTS
  Of the 20,279 study patients with prostate cancer, including 12,617 at intermediate risk and 7,662 at high risk, 71.3% received EBRT alone and 28.7% received EBRT plus brachytherapy. Median followup was 82 months (range 3 to 120) and median age was 70 years (range 36 to 90). On multivariate analysis compared to EBRT alone (75.6 to 81 Gy) EBRT plus brachytherapy was associated with improved survival (HR 0.75, p <0.001). This significance remained consistent for intermediate and high risk when analyzed separately (HR 0.73 and 0.76, respectively, each p <0.001). However on subset analysis compared to very high dose EBRT alone (79.2 to 81 Gy) in all patients combined EBRT plus brachytherapy was not associated with improved survival (HR 0.91, p = 0.083).
  
  
  CONCLUSIONS
  Compared to EBRT (75.6 to 81 Gy) we observed an association of EBRT plus brachytherapy with a decreased risk of death in men with intermediate and high risk prostate cancer. However this association was no longer significant when EBRT doses of 79.2 to 81 Gy were used.
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Arya
authors.initials: A
authors.lastname: Amini
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Bernard
authors.initials: B
authors.lastname: Jones
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Jackson
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Norman
authors.initials: N
authors.lastname: Yeh
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Timothy V
authors.initials: TV
authors.lastname: Waxweiler
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Paul
authors.initials: P
authors.lastname: Maroni
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Kavanagh
authors.affiliation: Department of Radiation Oncology and Division of Urology, Department of Surgery (PM), University of Colorado School of Medicine, Aurora, Colorado. Electronic address: david.raben@ucdenver.edu.
authors.forename: David
authors.initials: D
authors.lastname: Raben
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000379:methods*; D003120:Colorado / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D057216:Propensity Score; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000379:methods*; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D016896:Treatment Outcome
keywords: brachytherapy; dose-response relationship; mortality; prostatic neoplasms; radiation; radiotherapy