High cure rate with a moderately intensive treatment regimen in non-high-risk childhood acute lymphoblastic leukemia. Results of protocol ALL VI from the Dutch Childhood Leukemia Study Group.

PURPOSEHere we report the results of a nationwide cooperative study in the Netherlands on acute lymphoblastic leukemia (ALL) in children. The aim of the study was to improve the cure rate and to minimize side effects in a group of non-high-risk ALL patients, especially with regard to the CNS. A second aim was to study potential prognostic factors.METHODSChildren (age 0 to 15 years) with non-high-risk ALL (WBC count < 50 x 10(9)/L, no mediastinal mass, no B-cell phenotype, and no CNS involvement) were treated with a uniform protocol, ALL VI. The treatment protocol used 6-week induction regimen with three drugs (vincristine, dexamethasone, and asparaginase), three weekly doses of intravenous (IV) medium high-dose methotrexate (2 g/m2), and 2-year maintenance therapy that consisted of alternating 5-week periods of methotrexate and mercaptopurine and 2-week periods of vincristine and dexamethasone. In the first year of maintenance, triple intrathecal therapy was administered every 7 weeks.RESULTSFrom December...