To improve the accuracy of PSA values in the diagnosis of prostate cancer, PSA density and PSA velocity are useful concepts. PSA density takes into account the size of a man’s prostate gland when evaluating his PSA level. It is calculated by dividing the PSA value by the size of the prostate as determined by ultrasound. The numerical range of values is useful in differentiating prostate cancer from an enlarged benign prostate. Studies conclude that a PSA density value of greater than 0.15 indicates a higher cancer risk. In my own case, this value was useful in my cancer diagnosis since my prostate was not enlarged yet my PSA was in the high normal range. On the other hand, PSA velocity takes into account changes in a man’s PSA values over time which rise more rapidly in men with prostate cancer than in those without the disease. For more information and a summary of numerical values for PSA density and PSA velocity see the May 28th, 2014 article in Prostate Disorders from the Johns Hopkins Health Alerts.