FLAG Regimen with or without Idarubicin in Children with Relapsed/Refractory Acute Leukemia: Experience from a Turkish Pediatric Hematology Center

Objective: The optimal therapy to achieve higher rates of survival in pediatric relapsed/refractory acute leukemia (AL) is still unknown. In developing countries, it is difficult to obtain some of the recent drugs for optimal therapy and mostly well-known drugs proven to be effective are used. We assessed the efficacy of the combination of fludarabine, high-dose cytarabine, and granulocyte colony-stimulating factor (FLAG regimen) with or without idarubicin (IDA) in children with relapsed/refractory acute lymphoblastic leukemia and acute myeloid leukemia. Materials and Methods: Between September 2007 and May 2015, 18 children with refractory/relapsed AL attending our center, treated with a FLAG regimen with or without IDA, were included. The primary end point was the remission status of the bone marrow sampled after the first/second course of chemotherapy. The second end point was the duration of survival after hematopoietic stem cell transplantation (HSCT). Results: Complete remission (CR) was achieved in 7 patients (38.8%) after the first cycle, and at the end of the second cycle the total number of patients in CR was 8 (42.1%). All patients in CR underwent HSCT. The CR rate in patients who had IDA in combination therapy was 28.6%, and it was 50% in patients treated without IDA (p=0.36). Mean survival duration in transplanted patients was 24.7 +/- 20.8 months (minimum-maximum: 2-70, median: 25 months), and it was 2.7 +/- 1.64 months (minimum-maximum: 0-5, median: 3 months) in nontransplanted patients. Five of them (27.7%) were still alive at the end of the study and in CR. The median time of follow-up for these patients was 33 months (minimum-maximum: 25-70 months). Conclusion: FLAG regimens with or without IDA produced a CR of > 24 months in 27.7% of children with relapsed/refractory AL and can be recommended as therapeutic options prior to HSCT in developing countries.