Prostate biopsy patterns in the CaPSURE database: evolution with time and impact on outcome after prostatectomy.

PURPOSE: Significant variability exists in the urological community regarding the number of cores that should be taken during prostate biopsy. Using CaPSURE we determined trends in prostate biopsy patterns during the last decade and assessed whether changes in biopsy number have had an impact on outcomes after radical prostatectomy.
MATERIALS AND METHODS: In CaPSURE between 1995 and 2004 we identified 6,450 men with newly diagnosed prostate cancer who underwent biopsy with 6 cores or greater. The number of cores removed, number of cores positive for cancer and percent of cores containing cancer were analyzed by year of diagnosis. For 1,757 men who underwent radical prostatectomy these variables were entered into Cox proportional hazards models controlling for preoperative prostate specific antigen, biopsy Gleason sum and clinical stage to predict recurrence-free survival.
RESULTS: The mean number of removed cores increased from 6.9 in 1995 to 10.2 in 2004 (p <0.0001). The mean number of positive cores remained unchanged from 2.9 in 1995 to 3.2 in 2004 (p = 0.40). The percent of positive cores decreased from 42.6% in 1995 to 32.1% in 2004 (p <0.0001). The number and percent of positive cores were associated with recurrence-free survival after radical prostatectomy throughout the study period (each p <0.001).
CONCLUSIONS: The percent of positive cores is an independent predictor of disease recurrence after radical prostatectomy. The total number of tissue cores sampled increased during the last decade, thereby driving down the mean percent of positive cores from 42.6% to 32.1%. The trend toward an increasing number of removed cores may have contributed indirectly to improved outcomes after radical prostatectomy in the last decade.