21 October 2008
A recent study published in the journal European Urology suggests that a prostate cancer gene test may prove helpful in identifying patients in need of a repeat biopsy (see press release). Previous studies have shown that PCA3 messenger ribonucleic acid (mRNA) is over expressed in prostate cancer tissue and an assay for this gene could be an accurate means of predicting the results of a repeat biopsy. A study by Haese et al. has replicated these findings in a larger prospective study of 463 European men who had previously had negative biopsy results [Haese et al. (2008) Eur. Urol. 54(5):1081-1088]. The authors compared the levels of PCA3 mRNA in urine to repeat biopsy results, and showed that PCA3 levels were higher in men who had a positive biopsy results and were diagnosed with prostate cancer. Furthermore, their research also indicated a relationship between the PCA3 score and the significance of the cancer, suggesting it could be used as a means of identifying those patients who may need active surveillance. However, this finding needs to be evaluated further.
Comment: This new study demonstrates the clinical utility of using the PCA3 gene test and its superiority over a PSA assay in identifying those in need of a repeat biopsy. However, the relationship between PCA3 and prostate cancer is not absolutely clear, consequently for the present it will have to be used in conjunction with existing tests such as the PSA assay in order to reliably identify those at risk.