Background: There is currently no standard of treatment for patients with hormone refractory prostate cancer (HRPC) after failure of docetaxel-based chemotherapy. The purpose of this study was to assess the anticancer activity and tolerance of metronomic cyclophosphamide prednisolone combination in this setting.
Patients and methods: From 2005 to 2010, patients with HRPC who failed at least docetaxel-based chemotherapy were proposed metronomic cyclophosphamide-prednisolone regimen, and were prospectively registered. Twenty-three patients received 50 mg cyclophosphamide and 10 mg prednisolone per os daily until disease progression. Treatment tolerance and efficacy on PSA decrease and pain were studied.
Results: Metronomic cyclophosphamide prednisolone was safe, well tolerated, and demonstrated interesting clinical activity, yielding a prostate specific antigen decrease by ≥50% in 26% of patients and decrease by ≥30% in 48% of patients, but also favorable palliative effects on pain in 43% of patients. The median progression-free survival was 6 months (95% CI: 4-8 months) and the median overall survival was 11 months (95% CI: 7-19 months).
Conclusion: For this patient population, low dose metronomic cyclophosphamide prednisolone might be a viable alternative. Its convenient oral administration, low cost, and lack of toxicity justify further studies alone, or in combination with other agents in HRPC patients.