Combination therapy with VP16 and ethinylestradiol for hormone-refractory prostate cancer: Good response with tolerability

Objectives: This study evaluated the safety profile and therapeutic value of a combination therapy of etoposide and ethinylestradiol, which is a novel treatment protocol for patients with hormone-refractory prostate cancer (HRPC). Patients and Methods: Patients were given etoposide (25 mg/day, daily) and ethinylestradiol (3 mg/day, daily) orally until disease progression or unacceptable toxicity. The response rate, survival and safety profiles were evaluated. Results: Between 2003 and 2009, 61 patients were enrolled. In terms of PSA levels, >70% of patients showed a >50% reduction (complete response [CR] 51%, partial response 23%) and >90% showed a clinical response. Of 58 patients with measurable lesions, 24% (14/58) showed a CR, and most of these patients (13/14, 93%) survived without recurrence with median response duration of 28 months Conclusion: The regimen was tolerable, with a significant improvement in quality of life, and produced an effective response in patients with HRPC.