Metronomic chemotherapy with cyclophosphamide plus low dose of corticosteroids in advanced castration-resistant prostate cancer across the era of taxanes and new hormonal drugs

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.