Metronomic therapy with cyclophosphamide and dexamethasone for prostate carcinoma

The current study was designed to evaluate the efficacy and toxicity of the continuous oral administration of a combination of cyclophosphamide (50 mg/day given in the morning) and dexamethasone (1 mg/day given in the evening) in patients with prostate specific antigen (PSA) progression despite single or multiagent hormone therapy and antiandrogen withdrawal.

The authors retrospectively evaluated the medical records of all patients with prostate carcinoma who were treated with dexamethasone and cyclophosphamide and who were unable to participate in Phase II drug trials or had failed previous chemotherapy regimens.

Using clinical response guidelines set forth by the Prostate Specific Antigen Working Group, 29% of patients were found to have a > or = 80% reduction in PSA, 39% were found to have a 50-79% reduction in PSA, 6% were found to have a < 50% decrease in PSA, and 26% experienced disease progression while receiving treatment. The duration of response was 8 months (95% confidence interval [95% CI], 4-10 months). The duration of treatment was 9 months (95% CI, 6-14 months). The treatment was reported to be well tolerated with side effects being primarily bruising, Cushingoid facies, and gastrointestinal distress.

In the current study, low-dose dexamethasone and cyclophosphamide demonstrated efficacy as salvage therapy in the treatment of patients with hormone-refractory prostate carcinoma.