Prostate-Specific Antigen Levels and Prognosis in Patients with Hormone-Refractory Prostate Cancer Treated with Low-Dose Dexamethasone

Abstract

Objective: The efficacy of low-dose dexamethasone (DXM) therapy in patients with hormone-refractory prostate cancer (HRPC) was evaluated. Patients and Methods: Prostate-specific antigen (PSA) response and survival following DXM therapy were analyzed in 27 Japanese patients exhibiting HRPC. Concurrent therapies and antiandrogen withdrawal syndrome, which may affect PSA levels and palliative effects, were excluded from the study. A dose of 1.5 mg of DXM was administered, and androgen deprivation therapy was maintained during DXM therapy. A decline in PSA levels of at least 50% from baseline was considered a significant PSA response. Prognostic factors for PSA response and survival were examined by univariate and multivariate analyses. Results: A significant PSA response was observed in 16 of the 27 cases (59.3%). Median survival period of patients exhibiting significant PSA response was 15.9 months and was significantly longer than that of patients demonstrating a decline in PSA of less than 50% (median 7.7 months, p < 0.0001). Effect on pain control also correlated with the significant PSA response. No meaningful prognostic factors for PSA response were detected; however, a PSA decline of greater than 50% was the prognostic factor for survival. Conclusion: DXM therapy remains one of the most beneficial treatment modalities in patients with HRPC.