Comparison of prostate specific antigen velocity in screened versus referred patients with prostate cancer.

Purpose: Despite the tremendous stage migration associated with prostate cancer screening to our knowledge it remains unproven whether prostate specific antigen based screening decreases prostate cancer specific mortality. Recent studies have shown that prostate specific antigen velocity more than 2 ng/ml per year in the year before diagnosis is associated with a significantly greater risk of prostate cancer specific mortality after treatment. This may serve as a surrogate marker for prostate cancer outcomes. We compared the prostate specific antigen velocity profile between patients with prostate cancer in whom the tumor was detected in a formal screening study and those who were referred for treatment.
Materials and Methods: We evaluated prostate specific antigen velocity in 1,101 men from a prostate cancer screening study and in 368 not enrolled in a screening study who were referred for treatment. All patients underwent radical prostatectomy for clinically localized disease and had multiple preoperative prostate specific antigen measurements to calculate prostate specific antigen velocity.
Results: Median prostate specific antigen velocity before diagnosis was significantly higher in referred vs screened men (1.35 vs 0.68 ng/ml per year, p <0.0001). In addition, a significantly greater proportion of referred patients had prostate specific antigen velocity more than 2 ng/ml per year (38% vs 17%, p <0.0001). On multivariate analysis using prostate specific antigen, clinical stage and biopsy Gleason score screened vs referred status was a significant independent predictor of prostate specific antigen velocity more than 2 ng/ml per year (p <0.0004).
Conclusions: Prostate specific antigen velocity more than 2 ng/ml per year has been linked to a significantly greater risk of prostate cancer specific mortality. Patients who underwent serial screening had a more favorable prostate specific antigen velocity profile at diagnosis, suggesting that screen detected prostate cancer may be more likely to be cured with definitive therapy.