Treatment of erythroleukemia with anthracycline antibiotics and cytosine arabinoside.

The introduction of the anthracycline antibiotics and cytosine arabinoside have significantly improved the remission induction rate for patients with acute nonlymphocytic leukemia. Erythroleukemia (M6 by French-American-British classification) has long been considered to be resistant to chemotherapy. Since 1973 we have treated 14 patients with erythroleukemia with daunorubicin 45 mg/m2 or doxorubicin 30 mg/m2 for three days and cytosine arabinoside 100 mg/m2 by continuous infusion for 7 to 10 days. Six complete remissions (43%) were obtained with remission durations of 3+, 4+, 9, 13, 29+, and 35 months. While this remission rate is somewhat lower than that obtained with other types of acute nonlymphocytic leukemia, the combination of anthracycline antibiotics and cytosine arabinoside is clearly effective against erythroleukemia. Five patients treated before mid 1976 died soon after remission induction therapy was started. Four of these five patients were treated for 6 to 9 months with prednisone, halotestin, and/or splenectomy before remission induction chemotherapy was started and three of these patients died of systemic fungal infection, suggesting that these modalities of treatment may interfere with patient tolerance to remission induction therapy. It is suggested that erythroleukemia should be treated with intensive chemotherapy soon after the diagnosis is made.