PCA3: from basic molecular science to the clinical lab.

Prostate cancer is the second leading cause of cancer deaths in men in the United States. Use of the serum prostate specific antigen (PSA) test to screen men for prostate cancer since the late 1980s has improved the early detection of prostate cancer, however low specificity of the test translates to numerous false positive results and many unnecessary biopsies. New biomarkers to aid in prostate cancer diagnosis are emerging and prostate cancer gene 3 (PCA3) is one such marker. PCA3 is a noncoding RNA that is highly over-expressed in prostate cancer tissue compared to benign tissue. A non-invasive test for PCA3 was developed using whole urine collected after a digital rectal exam (DRE). Numerous clinical studies have demonstrated the utility of PCA3 for the diagnosis of prostate cancer and some studies suggest that PCA3 may also have prognostic value. The use of PCA3 in combination with serum PSA and other clinical information enhances the diagnostic accuracy of prostate cancer detection and will enable physicians to make more informed decisions with patients at risk for prostate cancer.