Consistency Of Gleason Grade Groups From Prostate Biopsy To Radical Prostatectomy

Purpose:To study the concordance of biopsy and radical prostatectomy Gleason grade group and independent predictors of upgrade and downgrade.Methods:We retrospectively evaluated 1281 patients who received prostate biopsy and radical prostatectomy at The First Affiliated Hospital of Zhejiang University between January 2013 and December 2018.Multivariate logistic regression model was used to analyze the independent predictors leading to upgrades or downgrades according to Gleason grade group system.Nomograms were established based on the logistic regression model with AUC and Horsmer-Lemeshaw test conducted to examine the discrimination and calibration of the models.Results:Among the 1281 patients included,371（29.0%）cases upgrades and 240（18.7%）downgrades.Biopsy Gleason grade group,PSAD≥0.25（OR=1.93）and clinical stage≥T_2b（OR=3.07）were independent predicting factors for upgrade while biopsy Gleason grade group,PSAD>0.5（OR=0.373）and clinical stage≥T_2c（OR=0.545）were independent predicting factors for downgrade.The nomograms were drawn with the above variables.The AUC of the model（0.777 for upgrade group,0.844 for downgrade group）and the Hosmer-Lemeshaw test results（P=0.687 for upgrade group,P=0.805 for downgrade group）show that the nomograms have good discrimination and calibration.Conclusion:Prostate biopsy Gleason group,PSAD and clinical stage are independent predictors of upgrade and downgrade.The nomograms may help clinicians to evaluate the accuracy of prostate biopsy but it still needs to be verified in clinical practice.