The aim of our study is to investigate the efficacy of metronomic cyclophosphamide plus low dose of corticosteroids in advanced or metastatic castration-resistant prostate cancer (CRPC) before, between, and after standard chemotherapy, such as docetaxel and cabazitaxel, and new hormonal treatments, such as abiraterone and enzalutamide. A retrospective analysis was performed on 37 patients. Cyclophosphamide was given orally 50 mg per day together with low dose of corticosteroids, namely dexametasone orally 1 mg per day or prednisone 10 mg per day. Seventeen patients (51%) showed a PSA decline≥ 50%. Median progression-free survival (PFS) and overall survival (OS) were 11 and 28 months, respectively. Median PFS and OS in the subgroup of patients with a PSA decline ≥ 50% were 14 and 35 months, respectively. Treatment was very well tolerated. We suggest that oral metronomic cyclophosphamide plus low dose of oral dexamethasone or prednisone may be a good and safe therapeutic option not only in those CRPC patients unfit for standard treatments but also in those heavily pre-treated patients.
Keywords: Castration-resistant; Cyclophosphamide; Metronomic chemotherapy; Prostate cancer.