Purpose: This study was designed to determine the toxicity of and response to idarubicin and cytosine arabinoside in children and adolescents with acute lymphoblastic leukemia (ALL) who had refractory or recurrent bone marrow disease.
Patients and methods: Patients <21 years of age with ALL in second or later bone marrow relapse or refractory to induction therapy were eligible. Some patients also had concurrent central nervous system (CNS) relapse. Therapy consisted of cytosine arabinoside, 1 g/m2/day given as a 6-h infusion, followed by bolus idarubicin, 5 mg/m2/day, both daily for 6 days. Children achieving remission received maintenance therapy with 3 days of etoposide, 100 mg/m2/day, followed by ifosfamide, 2.8 g/m2/day, alternating every 3 weeks with 3 days of cytosine arabinoside and idarubicin in the dosages described earlier. All courses of therapy were followed by granulocyte colony-stimulating factor (G-CSF). Removal from study to undergo bone marrow transplantation (BMT) was encouraged.
Results: Eighty-two patients were entered. There were 14 deaths (nine early), mostly from documented or presumed bacterial or fungal sepsis. Overall, 30 patients achieved complete remission (37%). These were mostly of brief duration--only one patient was still alive at 600+ days after BMT.
Conclusions: Cytosine arabinoside and idarubicin showed moderate activity in heavily pretreated children with ALL.