Idarubicin in induction treatment of acute myeloid leukemia in the elderly

The best approach to treatment of acute myeloid leukemia (AML) in elderly patients remains controversial. Intensive chemotherapy is the treatment of choice in selected patients, but age related changes might affect the pharmacokinetics of antineoplastic agents resulting in enhanced toxicity. We report our experience in elderly patients treated with idarubicin at attenuated doses plus cytarabine and etoposide.

Sixty-six AML patients, median age 66, with progressive disease and high tumor burden received idarubicin 8 mg/sqm i.v. d 1,3,5; cytarabine 200 mg/sqm by continuous i.v. infusion d 1-7; etoposide 60 mg/sqm i.v. d 1-5. A second course with the same drugs was planned irrespective of complete remission (CR) achievement. No consolidation was given; 44% had a documented preexisting myelodysplasia, 45% had a documented preexisting myelodysplasia, 45% presented with fever. Promyelocytic leukemias were excluded.

Thirty-five patients (53%) achieved CR and 9 PR for an overall response rate of 67%. Nine of them (13%) died early or during the aplastic phase. Preexisting myelodysplasia had no significant impact on CR achievement. Resistant disease was associated with CD7 phenotype and unfavorable karyotype. Overall survival and disease free survival were 14 and 13 months, respectively. The major toxicity consisted of infectious complications (WHO > 2 in 24% of patients). Six patients died for infection, 2 for heart failure, 1 for pulmonary embolism.

This induction regimen with attenuated doses of idarubicin is feasible and effective, but long-term survival remains an unresolved problem. Alternative post remission approaches are advisable in the aim of improving the remission duration.