Second national study AML-BFM 98 improved remission rate and overall survival in children with acute myeloid leukemia in the Czech Republic
Abstract
Between 1998 and 2004 the Czech Republic participated with Germany, Austria and Switzerland in the international AML-BFM 98 study on the treatment of children with acute myeloid leukemia (AML). Both standard risk and high risk patients received 5 blocks of intensive chemotherapy including 2 blocks of high-dose cytosine arabinoside, prophylactic cranial irradiation and maintenance treatment lasting for one year.
Randomized phase of treatment compared the classical consolidation of BFM protocols lasting for 6-weeks with two short blocks and assessed the role of G-CSF in the early phases of therapy. Treatment results were evaluated in 70 children divided into the standard risk (n = 34) and high risk (n = 36) groups according to the leukemia phenotype, genotype and early treatment response.
Six children (9%) had Down syndrome. Remission was achieved in 60 children (85.7%) representing 12% improvement in comparison with the previous AML-BFM 93 study.
Five children (7%) underwent either allogeneic (n = 4) or autologous (n = 1) bone marrow transplantation in the first remission. Nine children (15%) died in remission and 18 children (30%) suffered from relapse.
Two children developed secondary leukemia (sMDS and sALL); both were rescued by unrelated bone marrow transplantation. Five-year EFS/OS was 44.3/57.1% for the whole group of patients with a median follow-up 6.9 years (4.1-9.3 y).
EFS/OS in standard risk patients was 52.9/70.6%, in high risk 36.1/44.4%. The previous AML-BFM 93 study achieved 5-year EFS/OS 42.6/45.9% in the Czech Republic.
Altogether, 473 patients were enrolled in the international AML-BFM 98 study and 88% of them achieved complete remission with 5-year OS 62%. G-CSF reduced the duration of neutropenia but did not reduce the number and severity of infectious complications.
EFS of both consolidation arms was similar but length of the treatment and toxic deaths rate were reduced using blocks instead of classical consolidation. The participation in the international study increased requirements for the diagnostics and documentation and exposed the treatment results to the comparison with one of the world leading leukemia groups.