Initial cytoreduction by mitoxantrone and cytarabine has no impact on the outcome of interferon‐alfa‐2b therapy in chronic myelogenous leukemia

Abstract

Eleven previously untreated patients with chronic‐phase Philadelphia‐chromosome‐positive chronic myelogenous leukemia were treated with cytotoxic chemotherapy followed by interferon‐alfa‐2b (IFN‐α) maintenance. Initial chemotherapy consisted of three cycles of mitoxantrone 10 mg/m2 on day 1 and 2, and cytarabine 100 mg/m2 daily for 5 d. Complete hematological response was obtained in 9 (82%) patients with moderately associated toxicity. However, cytogenetic responses after three cycles were poor and transient (1 partial suppression and 2 minor suppression of Ph chromosome). Maintenance therapy with IFN‐α was started in 10 patients at 5 × 106 U/m2 daily with dose reduction if hematologic toxicity or severe side‐effects occurred. Of 9 evaluable patients treated for more than 3 months, 6 patients maintained a complete hematological response, whereas 1 patient remained in partial remission and 2 patients showed progressive disease. Cytogenetic evaluation showed partial suppression of Ph chromosome in 1 patient, whereas 1 patient had a minor response and 5 patients had no change or evolution of new chromosome abnormalities. As the results are not superior to IFN‐α treatment alone, it is concluded that initial cytoreduction by mitoxantrone and cytarabine has no impact on the outcome of therapy in CML.