Free PSA and the Free PSA to Total PSA Ratio as a Predictor of Response to Hormone Treatment for Metastatic Prostate Cancer / 대한비뇨기과학회지

ABSTRACT

PURPOSE: In this study we analyzed the changes of fPSA and f-PSA% and its prognostic significance in course of hormone treatment for metastatic prostate cancer. MATERIALS AND METHODS: We retrospectively analyzed 75 patients with metastatic prostate cancer who received maximal androgen deprivation therapy and in whom the fPSA and f-PSA% had been serially checked for at least 1 year. The patients were divided into two groups those patients with biological recurrence within 1 year, and those patients showing sensitivity to hormone therapy for longer than one year. Changes of the fPSA and f-PSA% in each group were analyzed in correlation with such prognostic factors as the PSA level and the Gleason sum. RESULTS: The initial PSA levels in each group were 508.0+/-331.4ng/ml and 39.8+/-7.6ng/ml, respectively and the fPSA levels were 59.4+/-19.4ng/ml and 6.7+/-4.1ng/ml, respectively; the group with early biological recurrence had significantly higher intial PSA and fPSA levels. The initial f-PSA% was relatively lower in the patients with early recurrence (0.123+/-0.41 vs 0.159+/-0.37, respectively), but the difference was not statistically significant. The PSA nadir and the fPSA nadir in the early recurrence group were 6.1 10.1ng/ml and 0.89 3.9ng/ml, respectively, and these were significantly higher compared to those values of the hormone sensitive group, i.e., 2.4+/-8.4ng/ml and 0.41+/-0.2ng/ml, respectively. In the early recurrence group, the f-PSA% changed from 0.123 to 0.092 and it gradually decreased during treatment. On the contrary, in the hormone sensitive group, the f-PSA% continuously increased during treatment, from 0.159 to 0.172. CONCLUSIONS: These findings suggest that fPSA and f-PSA% are influenced by hormone treatment and the pattern of changes in the fPSA and f-PSA% are different according to the responsiveness to hormone treatment.