MEC (mitoxantrone, etoposide and intermediate dose cytarabine): An effective induction regimen for previously untreated acute non-lymphocytic leukemia

Twenty-three patients with acute nor1 lymphocytic leukemia (ANLL), were treated with a single-6 day course of Mitoxantrone 6mg/m²/day, Etoposide 80mg/m² day and intermediate dose Cytarabine (ara-C) Ig/m²/day (MEC). Patients who achieved complete remission (CR) were submitted to a 4-day-course of MEC as consolidation. Seventeen patients (73.9% obtained CR, five patients (22.7% were resistant to the treatment and one patient died during induction. Median remission duration was 11 months; overall median survival was 16 months. Relapses occurred in 11 patients; eight patients are still alive: 6 in 1st, 2 in 2nd CR (mean survival 20.1 months, range 17-26). All patients experienced severe myelosuppression comparable to that observed after classical induction cycles including ara-C in continuous intravenous infusion; none, however, died of infection. Non-hematologic toxicity was minimal; in particular, neurotoxicity was not observed. According to our results, the MEC regimen, which was previously demonstrated to be active in refractory patients, represents an effective induction treatment in ANLL, with an acceptable toxicity.