Objectives: To develop probability nomograms to predict pathologic outcome at the time of radical prostatectomy (RP) on the basis of established prognostic factors and prostate biopsy quantitative histology.
Methods: Using information from the database of the Center for Prostate Disease Research (CPDR), univariate and multivariate analyses were performed on 1510 men who had undergone transrectal ultrasound and biopsy for diagnosis and had radical prostatectomy as primary therapy, with variables of age, race, clinical stage, pretreatment prostate-specific antigen (PSA), biopsy Gleason sum, and percentage of biopsy cores positive for cancer (total number of cores positive for cancer divided by the total number of cores obtained). The percentages of biopsy cores positive were grouped as less than 30%, 30% to 59%, and greater than or equal to 60%. The three most significant variables were used to develop probability nomograms for pathologic stage.
Results: PSA, biopsy Gleason sum, and percentage of cores positive were the three most significant independent predictors of pathologic stage. The assigned percentage of biopsy core-positive subgroups along with pretreatment PSA and highest Gleason sum were used to develop probability nomograms for pathologic stage.
Conclusions: Pretreatment PSA, highest biopsy Gleason sum, and the percentage of cores positive for cancer are the most significant predictors for pathologic stage after radical prostatectomy. On the basis of these findings, CPDR probability nomograms were developed to predict pathologic outcome at the time of RP.