Preoperative prediction of final pathological features is not improved by the free-to-total prostate-specific antigen ratio in Japanese men with clinically localized prostate cancer

BACKGROUND: The objective of the present study was to determine whether the percentage of free/total prostate-specific antigen (f/tPSA) in patients scheduled to undergo radical prostatectomy for clinically localized prostate cancer can preoperatively predict organ-confined versus extraprostatic disease. METHODS: Serum levels of fPSA and tPSA were measured in 97 patients with clinically organ-confined disease before they underwent radical prostatectomy. The relationships of tPSA, f/tPSA and the pathological stage of the prostatectomy specimens were analyzed. Furthermore, the ability of f/tPSA to predict the pathological features was compared with those of tPSA and systematic biopsy findings. RESULTS: Organ-confined and extraprostatic extension diseases were present in 51 and 46 men, respectively. tPSA in patients with extraprostatic diseases was significantly higher than that in those with organ-confined diseases; however, there was no significant difference in f/tPSA between these two groups. There was also a significant difference in tPSA levels at each pathological stage, while f/tPSA did not parallel the pathological stage. Furthermore, there was no additional information concerning the extent of prostate cancer obtained when f/tPSA was combined with tPSA or with the percent of positive biopsy cores, which is the most significant predictor of the extent of prostate cancer among factors associated with systematic biopsy. CONCLUSION: f/tPSA could not predict the final pathological features in patients with clinically localized prostate cancer before radical prostatectomy. Moreover, the predictive value provided by tPSA or systematic biopsy findings was not improved by combined analysis with f/tPSA.