title: The prognostic significance of Gleason scores in metastatic prostate cancer.
abstract: OBJECTIVE
  Although the majority of metastatic prostate cancer (mPCa) will arise from tumors with Gleason scores (GS) of 8 to 10 existing tumor grade analyses for mPCa have been almost uniformly limited to comparisons of ≤7 vs. ≥8. In this analysis, we comprehensively evaluate the GS as a prognostic factor for mPCa in the era of the updated Gleason grading system.
  
  
  METHODS
  The Surveillance, Epidemiology, and End Results (SEER) database was queried for patients with mPCa, GS 6 to 10, diagnosed from 2006 to 2008. GS and primary-secondary Gleason pattern variations were analyzed for overall survival and prostate cancer-specific survival (PCSS).
  
  
  RESULTS
  A total of 4,654 patients were evaluable. At 4 years, the overall survival rates were 51%, 45%, 34%, 25%, and 15% and PCSS rates were 69%, 57%, 44%, 33%, and 21% for GS 6, 7, 8, 9, and 10, respectively. Survival differences for GS 7 vs. 8, 8 vs. 9, and 9 vs. 10 were highly significant on both univariate and multivariate analyses accounting for age, prostate-specific antigen level, and T stage (all P<0.001). Gleason pattern 5 was an independent prognostic factor, both overall for patients with GS 6 to 10 and on primary-secondary Gleason pattern comparisons within the GS 8 (4+4 vs. 3+5 and 5+3) and GS 9 (4+5 vs. 5+4) subgroups. No survival differences were observed between 3+4 vs. 4+3. Overall, lower prostate-specific antigen level, younger age, and lower GS were associated with improved survival, with GS being the strongest prognostic factor for PCSS.
  
  
  CONCLUSIONS
  In this large population-based cohort, stratified survival outcomes were observed for GS 6 to 10, with sequential comparisons of GS 7 to 10, and the presence and extent of Gleason pattern 5 representing independent prognostic factors in the metastatic setting.
authors.affiliation: Department of Radiation Oncology, University of Colorado-Denver, Aurora, CO. Electronic address: chad.rusthoven@ucdenver.edu.
authors.forename: Chad G
authors.initials: CG
authors.lastname: Rusthoven
authors.affiliation: Department of Radiation Oncology, University of Colorado-Denver, Aurora, CO.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Carlson
authors.affiliation: Department of Radiation Oncology, University of Colorado-Denver, Aurora, CO.
authors.forename: Timothy V
authors.initials: TV
authors.lastname: Waxweiler
authors.affiliation: Department of Radiation Oncology, University of Colorado-Denver, Aurora, CO.
authors.forename: Norman
authors.initials: N
authors.lastname: Yeh
authors.affiliation: Department of Radiation Oncology, University of Colorado-Denver, Aurora, CO.
authors.forename: David
authors.initials: D
authors.lastname: Raben
authors.affiliation: Department of Medical Oncology, University of Colorado-Denver, Aurora, CO.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Flaig
authors.affiliation: Department of Radiation Oncology, University of Colorado-Denver, Aurora, CO.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Kavanagh
mesh_terms: D000368:Aged; D018572:Disease-Free Survival; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading / Q000706:statistics & numerical data*; D009362:Neoplasm Metastasis; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000401:mortality / Q000473:pathology*; D018426:SEER Program; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
chemical_list: D017430:Prostate-Specific Antigen
keywords: Gleason score; Histology; Metastasis; Prognosis; Prostate cancer