UPDATE - Issue 17 - April 2004
PSA research
The level of Prostate Specific Antigen (PSA) circulating in a man's blood stream is currently used as a diagnostic aid in the identification of prostate cancer. It is not the most perfect test in the world because of false positive readings and the difficulty of deciding what level should be interpreted as suspicious.
Often a man exhibiting a raised PSA has a normal result a few weeks later. Researchers have determined that an isolated elevation should be confirmed several weeks later before proceeding to further testing. This conclusion was arrived at after tracking the blood tests of 972 unscreened men over a five year period.
A small proportion of serum PSA is unbound or in its free form while most circulates in a complexed form, cPSA. Research on 831 men, 313 of whom were diagnosed with prostate cancer, suggests that cPSA would be a better initial test than total PSA (which is currently the standard measure) for the detection of prostate cancer and further urological evaluation. This new test would save many unnecessary biopsies.