Blood-based reverse transcriptase polymerase chain reaction assays for prostatic specific antigen: Long term follow-up confirms the potential utility of this assay in identifying patients more likely to have biochemical recurrence (rising PSA) following radical prostatectomy

Reverse transcriptase polymerase chain reaction (RT-PCR) assay is a sensitive technique to detect circulating cells expressing prostate-specific antigen (PSA) in blood or bone marrow from patients with prostate cancer. When applied to prostate cancer patients at our institution, this technique identifies those patients with a greater likelihood of extra-prostatic disease. We evaluated RT-PCR PSA as a predictor of PSA recurrence and compared it with pre-operative (serum PSA, digital rectal examination, Gleason score on biopsy) and post-operative parameters (pathological findings). Three hundred nineteen men scheduled for radical prostatectomy had an enhanced RT-PCR PSA assay before surgery. The enhanced RT-PCR PSA protocol has been previously described. PSA recurrence was defined as any serum PSA value above 0.2 μg/l. Forty-six patients had PSA recurrence. The mean follow-up was 25.4 months. Recurrence free survival was 53% for patients with positive RT-PCR PSA vs. 84% if RT-PCR PSA was negative. By using multivariate analyses, RT-PCR PSA status was not an independent predictor of PSA recurrence compared to pathological stage pT3, Gleason score on prostate specimen and serum PSA. If only pre-operative parameters were studied, serum PSA and RT-PCR PSA status were 2 independent pre-operative predictors of PSA recurrence compared with Gleason score on biopsy and digital rectal examination.