Detection of extraprostatic prostate cells utilizing reverse transcription-polymerase chain reaction

This article reviews the utility of reverse transcription-polymerase chain reaction (RT-PCR) in prostate cancer. RT-PCR aims to detect occult micromet astases in non-prostatic sites. Due to its exquisite analytical sensitivity , RT-PCR is able to amplify and detect even low-level, prostate-specific me ssages present at these extraprostatic sites. In recent years, a fair amoun t of data on the clinical utility of the technique had been reported. The t arget tissues under investigation are peripheral blood, bone marrow aspirat e, and lymph nodes. Favorite markers of choice are prostate-specific antige n (PSA), prostate-specific membrane antigen (PSMA), and human glandular kal likrein-2 (hK2). False positives among negative controls are low. For the m ost part, RT-PCR is inadequate in detecting tumor cells in the peripheral b lood from patients who are known to have metastatic prostate cancer. All st udies showed that RT-PCR could detect PSA, PSMA or hK2 mRNAs in the circula tion of patients who have organ-confined or extraprostatic disease. Most st udies showed that RT-PCR utilizing current markers could not be used as a p rospective test to diagnose prostate cancer. However, a few studies also sh owed that the detection rate could be predictive and sensitive enough to di fferentiate patients with organ-confined disease from those with extraprost atic disease. Data from PSA- or PSMA-RT-PCR using lymph nodes as the tissue source is more encouraging. RT-PCR was able to detect PSA and/or PSMA posi tive samples that have not been detected by conventional pathology. (C) 200 0 Wiley-Liss, Inc.