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.
European urology. 2016 Dec 13 [Epub ahead of print]
Blake B Anderson, Daniel T Oberlin, Aria A Razmaria, Bonnie Choy, Gregory P Zagaja, Arieh L Shalhav, Joshua J Meeks, Ximing J Yang, Gladell P Paner, Scott E Eggener
Section of Urology, University of Chicago, Chicago, IL, USA. Electronic address: ., Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA., Section of Urology, University of Chicago, Chicago, IL, USA., Department of Pathology, University of Chicago, Chicago, IL, USA., Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA., Section of Urology, University of Chicago, Chicago, IL, USA; Department of Pathology, University of Chicago, Chicago, IL, USA.