title: Prognostic Value of Percent Gleason Grade 4 at Prostate Biopsy in Predicting Prostatectomy Pathology and Recurrence.
abstract: The importance of primary Gleason grade among men with Gleason score 7 disease has been well-defined. However, this dichotomization may oversimplify the continuous spectrum of absolute percent Gleason grade 4 disease (G4%). In this study we report the prognostic value of G4% in cancer related outcomes of men undergoing radical prostatectomy.
  
  
  
  Patients who underwent radical prostatectomy for clinically localized Gleason 6-8 prostate cancer from 2005 to 2013 were included in the study. G4% was determined as biopsy tumor length containing Gleason pattern 4/total tumor length, which performed better than alternative quantifications of pattern 4 involvement. G4% was correlated with time to biochemical recurrence and presence of adverse radical prostatectomy pathology, defined as primary Gleason 4 or pT3 or greater, by multivariable Cox and logistic regressions.
  
  
  
  Of 1,691 patients 517 (30.6%) had adverse pathological features and 86 (5.6%) experienced biochemical recurrence. On multivariable analyses G4% was a significant predictor of adverse pathology (OR 1.04, 95% CI 1.03-1.05) and time to biochemical recurrence (HR 1.02, CI 1.01-1.03). G4% was also a significant independent predictor of adverse pathology in subsets of patients with Gleason score 7 (OR 1.05, 95% CI 1.03-1.06), 3+4 (OR 1.06, 95% CI 1.04-1.08) and 4+3 cancer (OR 1.05, 95% CI 1.03-1.06). We found a significantly increased risk of adverse pathology at potentially meaningful G4% thresholds (1% to 10% vs 20% to 30%).
  
  
  
  The incremental percentage of Gleason grade 4 disease in biopsy specimens is an important predictor of adverse pathology and biochemical recurrence across the entire range of G4% disease. Accounting for G4% can improve risk assessment even among those patients with Gleason 3+4 or 4+3 cancer and may help inform patient counseling.
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Adam I
authors.initials: AI
authors.lastname: Cole
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Morgan
authors.affiliation: Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Spratt
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Ganesh S
authors.initials: GS
authors.lastname: Palapattu
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Chang
authors.initials: C
authors.lastname: He
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Tomlins
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Alon Z
authors.initials: AZ
authors.lastname: Weizer
authors.affiliation: Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Felix Y
authors.initials: FY
authors.lastname: Feng
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Angela
authors.initials: A
authors.lastname: Wu
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Javed
authors.initials: J
authors.lastname: Siddiqui
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Arul M
authors.initials: AM
authors.lastname: Chinnaiyan
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Montgomery
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Lakshmi P
authors.initials: LP
authors.lastname: Kunju
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: David C
authors.initials: DC
authors.lastname: Miller
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Brent K
authors.initials: BK
authors.lastname: Hollenbeck
authors.affiliation: Department of Urology, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: John T
authors.initials: JT
authors.lastname: Wei
authors.affiliation: Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan. Electronic address: mrohit@med.umich.edu.
authors.forename: Rohit
authors.initials: R
authors.lastname: Mehra
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis / Q000473:pathology*; D011379:Prognosis; D016016:Proportional Hazards Models; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies
keywords: biopsy; neoplasm grading; prostatectomy; prostatic neoplasms; recurrence