New Marker for Prostate Cancer Found
Testing for protein could make earlier detection possible, researchers say
THURSDAY, March 11, 2004 (HealthDayNews) -- Testing for a protein called EPCA that signals the early presence of prostate cancer could help doctors detect the disease up to five years sooner than it can now be diagnosed.
That good news is reported in the March issue of the Journal of Urology.
EPCA is a marker protein that indicates the earliest cell changes that occur during cancer development.
The study authors suggest that testing for EPCA could serve as an adjunct to the current diagnostic approach -- repeat needle biopsies -- used for men with elevated prostate-specific antigen (PSA) levels. PSA is a substance released by the prostate gland that can be detected in blood. PSA is commonly used to check for signs of prostate cancer and other prostate problems.
"One of the problems with testing for levels of PSA as an indicator of prostate cancer is that PSA levels often fluctuate up and down, making it difficult to know for certain whether a man has prostate cancer without performing multiple biopsies over time," study author Robert Getzenberg, a professor of urology, pathology and pharmacology at the University of Pittsburgh School of Medicine, says in a prepared statement.
"By testing for EPCA in men with high levels of PSA, we may be able to detect the presence of prostate cancer earlier, before it is discoverable by biopsy, saving patients the fear and stress of repeat procedures and enabling us to treat the disease sooner," Getzenberg says.
He and his colleagues compared 29 tissue samples from men with prostate cancer who had initial negative biopsies with tissue samples from 27 healthy men. They found the samples from the negative biopsies of men who were later diagnosed with prostate cancer expressed EPCA. They did not detect EPCA in the biopsy sample of men who remained free of prostate cancer.
The study also found EPCA wasn't confined to the tumor in men with prostate cancer. The protein was also expressed throughout the prostate. That indicates that EPCA may be useful as a prognostic marker for prostate cancer.
Researchers are now conducting a multi-center study to further assess EPCA and its potential use as a biomarker for prostate cancer.
The American Cancer Society has more about prostate cancer.