Hormonal sensitivity following endocrine withdrawal in hormone-refractory prostate cancer

BACKGROUND: Prostate cancer is proposed to be classified according to hormonal sensitivity. The purpose of this study is to examine hormonal sensitivity of the patient with refractory prostate cancer subsequent to primary hormonal therapy. METHODS: Sixteen patients with refractory prostate cancer subsequent to primary combination hormonal therapy were enrolled in this study. All 16 patients with progressive disease after elimination of oral hormonal agents or after response following hormonal withdrawal received dexamethasone (DXM) (initially 1.5 or 1.0 mg, then tapered to 0.5 mg) orally not only for the purpose of second-line hormonal therapy but also as an indicator of hormonal sensitivity. RESULTS: Overall, 4 patients showed a prostate-specific antigen (PSA) decrease of >50% from baseline on discontinuation of hormonal agents, while another 7 patients showed a PSA decrease of <50%. Five patients showed PSA level was progressed after the withdrawal. In all patients with PSA values that decline not only >50% but also <50% following oral endocrine withdrawal, the fall in PSA values had been >50% following DXM administration. However, the PSA value in the patients with PSA progression following the oral endocrine withdrawal kept rising after DXM administration. CONCLUSIONS: The findings in this study would just suggest a possible relationship between DXM sensitivity and the response to endocrine withdrawal. The patients whose PSA values decline following oral endocrine withdrawal may maintain hormonal sensitivity.