Results of acute lymphoblastic leukemia therapy in childhood with a modified BFM protocol in a multicenter study in the German Democratic Republic.

Between 1 September 1981 and 31 December 1985, 382 previously untreated children with ALL were entered into study VII/81, a multicentric and randomized study with a modified BFM protocol. Patients were divided into three risk groups according to the initial lymphoblast count and liver and spleen enlargement: standard- (SR), medium- (MR), and high-risk (HR) groups. Of all patients, 94% attained complete remission. The actuarial probability of event-free survival is 0.62 +/- 0.04 (SR group, 0.66 +/- 0.06; HR group, 0.29 +/- 0.12). Sixty-one patients relapsed, 10 had isolated CNS relapses, and 11 CNS relapses were combined with bone marrow relapses. Concerning the duration of maintenance therapy, patients were randomized into two groups of 18 and 24 months respectively. Up to now, there has been a slight advantage for the 18-month group. Two different methods of CNS preventive therapy for SR patients (irradiation plus intrathecal methotrexate and intermediate-dose methotrexate (IDMTX) plus intrathecal methotrexate) were used and revealed a higher rate of CNS relapses but a lower rate of bone marrow relapses in the intermediate-dose MTX group.