Continuous High-Dose Idarubicin and Busulfan As Conditioning Regimen for Chinese Patients with Acute Myeloid Leukemia Undergoing Autologous Stem Cell Transplantation

To investigate the efficacy and toxicity of continuous high-dose idarubicin and busulfan as conditioning regimen for Chinese patients with acute myeloid leukemia (AML) undergoing autologous stem cell transplantation (ASCT).

A total of 27 patients with AML were enrolled in our prospective study, including 25 of first complete remission and 2 of second complete remission. Twelve patients were male, and 15 were female, with ages ranging from 14 to 56 (median, 31) years. All the patients were given induction and consolidation treatments and underwent ASCT receiving a continuous infusion of high-dose idarubicin (20 mg/m² qd, days -13 to -11) and busulfan (oral busulfan 1 mg/kg q6h or intravenous busulfan 0.8 mg/kg q6h, d-5∼-2) as conditioning regimen.

All the patients acquired hematopoietic reconstitution. The median number of days to neutrophil (©ƒ0.5×10⁹/l) and platelet (©ƒ20×10⁹/l) recovery was 10 and 12, respectively. After a median follow-up of 23 months from diagnosis, the median overall survival (OS) and the median disease-free survival (DFS) were 19(7∼87) and 15(6∼85) months, respectively. A total of 18 patients (73.4%) are alive (17 in continuous complete remission) and 10 (37.4%) relapsed after transplant. Those who underwent standard dose of idarubicin (12 mg/m² qd, days1–3) and cytarabine (100∼200 mg/m² qd, days1–7) as induction treatment showed lower relapse rate and better OS and DFS as compared to other induction regimens without significant difference. Patients with favorable karyotypes and molecular biological types acquired better OS and DFS as compared to those with intermediate karyotypes and molecular biological types, but there was no significant difference. Myelosuppression and infections due to neutropenia was the most frequent adverse effects, severe nonhematologic toxicity was not observed in all patients. The patients in our study acquired similar OS and DFS compared to those with intermediate karyotypes and molecular biological types who underwent allogeneic transplantation (HLA identical sibling donor) in first complete remission, and the side effects were minor.

Continuous high-dose idarubicin and busulfan as conditioning regimen for Chinese patients with AML undergoing ASCT was effect and well tolerable.

No relevant conflicts of interest to declare.