Long-term survival after induction therapy with idarubicin and cytosine arabinoside for de novo acute myeloid leukemia

We treated 153 patients with de novo acute myeloid leukemia (AML) with two induction courses of conventional-dose cytosine arabinoside (ara-C) and idarubicin (AIDA) followed by either a third course of AIDA, high-dose ara-C or bone-marrow transplantation. The complete remission (CR) rate for all patients was 63.4%, with a higher CR rate for patients with a normal (versus unfavorable) karyotype (73.2% vs 52.5%; P=0.038). The probability of overall survival (OS) was 30.7% after 5 years (26.3% after 7 years). Improved OS at 5 years could be observed for patients up to 50 years old versus patients older than 50 years of age (37.6% vs 19.9%; P=0.001) and patients with a normal (versus unfavorable) karyotype (42.9% vs 14.1%; P=0.0016). Disease-free survival (DFS) after 5 years was 33.2% for all 97 CR patients and was significantly better for patients with a normal (versus unfavorable) karyotype (44.3% vs 12.3%; P=0.003). Multivariate analysis revealed that the age for OS (P<0.02) and the karyotype for both OS (P<0.03) and DFS (P< 0.05) were independent prognostic factors. In conclusion, AIDA is an effective and well-tolerated induction regimen (even in elderly patients) with a 5-year survival of more than 30% when combined with ara-C-containing postremission therapy. The karyotype is the most powerful prognostic factor for predicting the outcome of patients treated with this protocol.