A study by researchers at New York-Presbyterian Hospital/Weill Cornell Medical Center, shows that PSA can be a much more effective marker for prostate cancer when an additional drug therapy is used, than it can as a stand-alone test, which is how it is currently used by physicians.
"At a time when the value of PSA is being increasingly debated, we have shown that when used in a specific way, it can be of great value in identifying men with previously undetected prostate cancer," the lead author of the study Dr Steven A Kaplan said.
"We have shown that using PSA with these drugs can help us differentiate prostate cancer from benign prostate disease in patients who are difficult to diagnose," Kaplan said, adding "it also demonstrates a better way to use both the PSA test and these powerful drugs."
The researcher created the combination screening method as a way to understand cancer risk in men who have consistently abnormal PSA readings despite one or more negative biopsies.
He adds that the PSA (prostate specific antigen) test alone is not a good indicator of prostate cancer. "It measures multiple factors associated with prostate disease, including enlargement of the prostate and inflammation."
The theory is that these drugs might improve the usefulness of PSA in diagnosing prostate cancer. If the PSA remains persistently high even though the prostate has shrunk, or PSA rises after having reached its lowest level, it could indicate the presence of cancer. And when the gland is smaller, a biopsy can be more effective, according to researchers.
The study was conducted in two phases enrolling 276 men at the medical center whose PSA was greater than 4, who had a normal digital rectal examination and two or more negative biopsies.
The findings showed that a year of the drug therapy reduced PSA in all the men, an average of 48 per cent, but the magnitude of reduction was significantly greater in men with benign prostate disease and significantly less in 28 per cent of the patients whose prostate biopsy detected cancer.
The findings of the study were published in the Journal of Urology.
