title: Retrospective evaluation reveals that long-term androgen deprivation therapy improves cause-specific and overall survival in the setting of dose-escalated radiation for high-risk prostate cancer.
abstract: OBJECTIVE
  To evaluate the role of androgen deprivation therapy (ADT) and duration for high-risk prostate cancer patients treated with dose-escalated radiation therapy (RT).
  
  
  METHODS
  A retrospective analysis of high-risk prostate cancer patients treated with dose-escalated RT (minimum 75 Gy) with or without ADT was performed. The relationship between ADT use and duration with biochemical failure (BF), metastatic failure (MF), prostate cancer-specific mortality (PCSM), non-prostate cancer death (NPCD), and overall survival (OS) was assessed as a function of pretreatment characteristics, comorbid medical illness, and treatment using Fine and Gray's cumulative incidence methodology.
  
  
  RESULTS
  The median follow-up time was 64 months. In men with National Comprehensive Cancer Network defined high-risk prostate cancer treated with dose-escalated RT, on univariate analysis, both metastasis (P<.0001; hazard ratio 0.34; 95% confidence interval 0.18-0.67; cumulative incidence at 60 months 13% vs 35%) and PCSM (P=.015; hazard ratio 0.41; 95% confidence interval 0.2-1.0; cumulative incidence at 60 months 6% vs 11%) were improved with the use of ADT. On multivariate analysis for all high-risk patients, Gleason score was the strongest negative prognostic factor, and long-term ADT (LTAD) improved MF (P=.002), PCSM (P=.034), and OS (P=.001). In men with prostate cancer and Gleason scores 8 to 10, on multivariate analysis after adjustment for other risk features, there was a duration-dependent improvement in BF, metastasis, PCSM, and OS, all favoring LTAD in comparison with STAD or RT alone.
  
  
  CONCLUSIONS
  For men with high-risk prostate cancer treated with dose-escalated EBRT, this retrospective study suggests that the combination of LTAD and RT provided a significant improvement in clinical outcome, which was especially true for those with Gleason scores of 8 to 10.
authors: Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-5010, USA. ffeng@med.umich.edu
authors: Felix Y
authors: FY
authors: Feng
authors: Kevin
authors: K
authors: Blas
authors: Karin
authors: K
authors: Olson
authors: Matthew
authors: M
authors: Stenmark
authors: Howard
authors: H
authors: Sandler
authors: Daniel A
authors: DA
authors: Hamstra
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D000726:Androgen Antagonists / Q000627:therapeutic use*; D003131:Combined Modality Therapy / Q000379:methods / Q000401:mortality; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists