title: Extraprostatic Extension Is Extremely Rare for Contemporary Gleason Score 6 Prostate Cancer.
abstract: A significant proportion of men with Gleason score 6 (GS6) prostate cancer undergo treatment with radiation or surgery.
  
  
  
  To assess pathologic stage of pure GS6 at radical prostatectomy (RP).
  
  
  
  In the period 2003-2014, 7817 patients underwent RP at two institutions. Of 2502 patients with GS6 at surgery, 60 were identified as stage pT3a-b on initial pathologic review, 55 with pT3a (extraprostatic extension, EPE), and five with pT3b (seminal vesicle invasion; SVI). All cases of GS6 with pT3 disease underwent contemporary pathologic evaluation for Gleason grade, stage, and extent of EPE. At one institution, all GS≥7 pT3b cases were re-reviewed for downgrading. The 2014 International Society of Urological Pathology (ISUP) Gleason grading criteria and 2009 ISUP recommendations on pT3 staging were applied.
  
  
  
  Calculated incidence (%) of pT3a, pT3b, pT4, and lymph node-positive disease.
  
  
  
  Of the 60 GS6 pT3a-b cases identified in the period 2003-2014, seven (0.28% of entire GS6 cohort) with GS6 and pT3a were identified after re-review, all focal EPE. Among the re-examined cohort, no cases of GS6 with pT3b were observed. None of the 132 GS≥7 pT3b cases were downgraded to GS6. Limitations include partial embedding of specimens and separate pathologic review at each institution.
  
  
  
  In a large prostatectomy cohort, GS6 never had seminal vesicle invasion (0%) and was very rarely (0.28%) associated with extraprostatic extension.
  
  
  
  GS6 prostate cancer rarely spreads outside the prostate. A new finding in this study was that GS6 prostate cancer never spread to the seminal vesicles.
authors.affiliation: Section of Urology, University of Chicago, Chicago, IL, USA. Electronic address: Blake.Anderson@uchospitals.edu.
authors.forename: Blake B
authors.initials: BB
authors.lastname: Anderson
authors.affiliation: Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Oberlin
authors.affiliation: Section of Urology, University of Chicago, Chicago, IL, USA.
authors.forename: Aria A
authors.initials: AA
authors.lastname: Razmaria
authors.affiliation: Department of Pathology, University of Chicago, Chicago, IL, USA.
authors.forename: Bonnie
authors.initials: B
authors.lastname: Choy
authors.affiliation: Section of Urology, University of Chicago, Chicago, IL, USA.
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Zagaja
authors.affiliation: Section of Urology, University of Chicago, Chicago, IL, USA.
authors.forename: Arieh L
authors.initials: AL
authors.lastname: Shalhav
authors.affiliation: Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Meeks
authors.affiliation: Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Ximing J
authors.initials: XJ
authors.lastname: Yang
authors.affiliation: Section of Urology, University of Chicago, Chicago, IL, USA; Department of Pathology, University of Chicago, Chicago, IL, USA.
authors.forename: Gladell P
authors.initials: GP
authors.lastname: Paner
authors.affiliation: Section of Urology, University of Chicago, Chicago, IL, USA.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Eggener
mesh_terms: D000368:Aged; D001706:Biopsy; D002641:Chicago; D016208:Databases, Factual; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery
keywords: Male; Neoplasm grading; Prostatectomy; Prostatic neoplasms; Seminal vesicles