PSA is the best cancer tumor marker in all of medicine, but there is understandable pressure to improve its accuracy. Prior to the development of the fPSA test, men in this group were routinely recommended for a prostate biopsy, which can be both painful and costly. While all three methods increased the accuracy of total PSA testing in distinguishing benign prostatic conditions from prostate cancer, age-specific PSA cutoffs were less sensitive than fPSA and missed 20 percent to 60 percent of all cancers in men over 60 years of age. In addition, the fPSA ratio and PSA density tests both had a 95 percent cancer detection rate when the fPSA ratio of 25 percent and a PSA density level of 0.078 were used. The study also found both methods equally effective at predicting cancer aggressiveness.
Prostatic biopsy is required for actual diagnosis of prostate cancer.
They are as accurate as PSA density tests in the study, but less costly. Other studies have also shown that free PSA ratios can provide the bonus of telling patients and physicians how aggressive the cancer is. The study was supported by a research grant from a subsidiary of Beckman Coulter. Beckman Coulter, headquartered in Fullerton, Calif., is a leading provider of instrument systems and complementary products that simplify and automate processes in life science and clinical laboratories. The company's products are used throughout the world in all phases of the battle against disease, from pioneering medical research and drug discovery to diagnostic testing that aids in patient treatment.