Background: In Hungary children (from 1 to 18 years of age) with de novo acute lymphoblastic leukemia were treated from January 1996 to October 2002, according to protocol ALL-BFM-95.
Aim: The aim of this study was to evaluate the experience with this protocol, the treatment results according to the risk groups and to compare the Hungarian data with the international results.
Methods: Patients were stratified into 3 risk groups, based on initial white blood cell count, age, immunology, cytogenetics and response to treatment: standard, medium and high risk group.
Results: Three hundred sixty eight children entered the study (male-female ratio was 1.27:1, median age 6 years and 4 months). 110 (29.9%) children were in the standard, 210 (57.1%) in the medium and 48 (13%) in the high risk group. Duration of the chemotherapy was 2 years, except of the boys in the standard risk group, their maintenance therapy was 1 year longer. The overall complete remission rate was 93.2%. 20 (5.4%) children died in induction and 5 (1.4%) were non-responders. The 5-year overall survival for all patients was 78.5%, in the standard risk group 93.2%, in the medium risk group 78.4% and in the high risk group 44.5% with a minimum follow up of 1.19 years and median follow up of 4.85 years. From the 368 patients 272 (73.9%) are still in their first complete clinical remission and other 18 children are alive after relapse. In 14.7% of the patients relapse was diagnosed; the most common site was the bone marrow. In one patient second malignancy occurred. The 5-year event free survival for all patients was 72.6%, in the standard risk group 87.6%, in the medium risk group 72.1% and in the high risk group 39.9%.
Conclusion: The treatment outcome of children with acute lymphoblastic leukemia improved remarkably over the last decades. 78% of children suffering from acute lymphoblastic leukemia could be cured with the ALL-BFM-95 protocol. The Hungarian results are comparable to those achieved by other leukaemia study groups in the world regarding the ALL-BFM-95 protocol.