MP51-13 EXTERNAL VALIDATION OF THE QUANTITATIVE GLEASON SCORE IN PREDICTING PROSTATE CANCER RECURRENCE AFTER RADICAL PROSTATECTOMY (2014)

You have accessJournal of UrologyProstate Cancer: Localized V1 Apr 2014MP51-13 EXTERNAL VALIDATION OF THE QUANTITATIVE GLEASON SCORE IN PREDICTING PROSTATE CANCER RECURRENCE AFTER RADICAL PROSTATECTOMY Adam Reese, Elen Woldemichael, Matthew Cooperberg, and Joel Nelson Adam ReeseAdam Reese More articles by this author , Elen WoldemichaelElen Woldemichael More articles by this author , Matthew CooperbergMatthew Cooperberg More articles by this author , and Joel NelsonJoel Nelson More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.1669AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail Introduction and Objectives The quantitative Gleason score (qGS) is a modification of the current Gleason grading system for prostate cancer, based on the weighted average of high vs. low grade tumor in a pathology specimen. The qGS aims to capture the continuum of risk associated with higher volumes of poorly differentiated disease. The value of the qGS in predicting biochemical recurrence (BCR) after radical prostatectomy (RP) has been previously reported in a single institution series. This study aims to validate the predictive ability of the qGS in an external dataset. Methods We identified patients who underwent RP at the University of Pittsburgh Medical Center between 1999 and the present, and were found to have a traditional Gleason score (tGS) of 3+4 or 4+3 on final pathology. The qGS was calculated in these men according to the following equation: qGS = 2 x [(3 x %Gleason pattern 3) + (4 x %Gleason pattern 4)] Time to BCR after RP was determined. Using Kaplan-Meier (KM) and Cox proportional hazards regression, we compared the ability of qGS vs. tGS to predict BCR after RP. Results 1277 men met the study inclusion criteria. Using the tGS, 1034 (81%) were pathological Gleason 3+4 and 243 (19%) were Gleason 4+3. Over a median of 56 months, 133 (10%) patients developed BCR. In KM analysis, the qGS allowed for a finer assessment of BCR risk compared to the tGS (see figures 1&2). In multivariable analysis the qGS was significantly associated with BCR (HR 5.24, 95% CI 3.49-7.87). The c-index for the qGS model exceeded that of the tGS model (0.85 vs. 0.83). In a model incorporating both the qGS and the tGS, the qGS remained significantly associated with BCR (P<0.01), whereas the tGS was not (p=0.78). Conclusions The qGS is a simple modification of the Gleason grading system, based on the weighted average of Gleason patterns present in the pathology specimen. This external validation confirms the ability of the qGS to predict BCR after RP with greater precision than the tGS. The qGS may help to identify men at high risk of recurrence who may benefit from adjuvant therapy after RP. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e602 Peer Review Report Advertisement Copyright & Permissions© 2014MetricsAuthor Information Adam Reese More articles by this author Elen Woldemichael More articles by this author Matthew Cooperberg More articles by this author Joel Nelson More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...