Relationships between reverse transcriptase-polymerase chain reaction for prostate specific antigen, survival, and various prognostic laboratory factors in patients with hormone refractory prostate cancer

Abstract

The detection of prostate-specific antigen (PSA) mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR) in the bloodstream of prostate cancer patients has been hypothesized as a prognostic marker, however little data are available concerning the association between this molecular marker and other laboratory values of potential importance. In this study, in patients with hormone-refractory prostate cancer (HRPC), relationships were determined between PSA RT-PCR positivity, survival, and various relevant markers including serum PSA, LDH, albumin, alkaline phosphatase and hemoglobin. A total of 19/30 HRPC patients were positive for PSA by RT-PCR. Positivity was significantly linked to serum PSA ( P = 0.004) and serum alkaline phosphatase ( P = 0.026) but not to the other laboratory variables. Median survival time for RT-PCR-positive patients was 9 months, compared to 19 months for RT-PCR-negative patients ( P = 0.035). Median survival time for patients with a hemoglobin ≥11 g/dL was 12 months, compared to 9 months for patients with <11 g/dL ( P = 0.005). Dichotomized (≥ or < median) serum PSA, LDH, alkaline phosphatase, and albumin were not significantly associated with survival in univariate analyses. In multivariate analysis, only dichotomized hemoglobin (<11g/dL vs. ≥11g/dL) remained statistically significant ( P = 0.019), indicating that RT-PCR had no independent association with survival after controlling for hemoglobin status in this study.