Can Prostate Specific Antigen Velocity Thresholds Decrease Insignificant Prostate Cancer Detection?

Abstract

A controversy of current prostate specific antigen based prostate cancer screening is the over detection of potentially insignificant prostate cancer. Because PSA kinetics were previously linked to prostate cancer specific mortality, we determined whether prostate specific antigen velocity is associated with clinically significant prostate cancer. A total of 1,073 men underwent radical prostatectomy from 1992 to 2008 with data available on prostate specific antigen velocity and tumor volume. Insignificant cancer was defined by the Ohori criteria as organ confined, tumor volume 0.5 cc or less and no primary or secondary Gleason pattern 4 or 5. We calculated the proportion of men with pathologically insignificant prostate cancer stratified by prostate specific antigen velocity. Preoperative prostate specific antigen velocity greater than 0.4 ng/ml per year was significantly associated with high grade disease (p = 0.008), positive surgical margins (p = 0.003) and seminal vesicle invasion (p = 0.007) at radical prostatectomy. Median tumor volume was also significantly higher in men with preoperative prostate specific antigen velocity greater than 0.4 ng/ml per year (3.1 vs 2.4 cc, p = 0.0001). Overall 69 men (6%) met the Ohori criteria for insignificant cancer. Patients with preoperative prostate specific antigen velocity greater than 0.4 ng/ml per year were 50% less likely to have insignificant disease (10% vs 5%, p = 0.003). A prostate specific antigen velocity threshold of 0.4 ng/ml per year was associated with the likelihood of insignificant prostate cancer. This suggests that prostate specific antigen velocity may be a useful adjunct in prostate cancer screening to increase specificity for identifying patients with clinically significant disease.