Vol 14, No 1 (2015)

The paper presents the main stages in the evolution of therapy for acute lymphoblastic leukemia (ALL) in children and adolescents all over the world and in Russia and outlines the history of BFM-oriented protocols. The formation of the national cooperative group for ALL treatment in Russia and the creation of Moscow-Berlin protocols are described and approaches to optimization of ALL therapy in children and adolescents in Russia are presented.

This paper presents the results of randomized study of the efficacy of two glucocorticosteroids (GCS) in induction therapy of children and adolescents with acute lymphoblastic leukemia (ALL). A total of 1064 primary patients with ALL, aged 1-18 years, were registered from 18.04.2002 to 15.11.2006 in Russia and Belarus Republic. Randomization was carried out before induction therapy. The patients received the dexamethasone (Dexa; 6 mg/m²) “sleeve” of ALL-MB 2002 protocol (n = 539) or the methylprednisolone (MePred; 60 mg/m²) “sleeve” of the protocol (n = 525). The survival rates virtually did not differ: 10-year event-free survival (EFS) was 73 ± 2% in the Dexa group vs. 70 ± 2% in MePred group, p = 0.260; 10-year overall survival (OS) was 79 ± 2 and 77 ± 2%, respectively; p = 0.232; the incidence of relapses after ALL induction therapy by different GCS virtually did not differ. The incidence of isolated central nervous system relapses (1.7% in patients receiving Dexa and 3% in patients treated by MePred; p = 0.138) and of combined relapses with central nervous system involvement differed just negligibly (3.2% in Dexa group and 3.4% in MePred group; p = 0.937). The induction mortality was also similar (3.2% in Dexa group and 3.8% in MePred group; p = 0.677). Retrospective comparison in different age groups showed predominant efficacy of Dexa in children under 14 years of age. This fact deserves further research in prospective randomized multicenter studies.

The transcription and immunological studies of the latest decade have shed new light on the biology of T-cell acute lymphoblastic leukemia (T-ALL) and identified a new T-ALL subtype - early T-cell precursor ALL (ETP-ALL), a tumor from immature hematopoietic precursors which retain their capacity to myeloid differentiation. Identification of the characteristic phenotype of immature T-lymphoblasts is extremely important for the diagnosis of ETP-ALL, when the risk of failure of therapy even by modern protocols is very high. By transcription ETP-ALL is closely related to hematopoietic stem cells and myeloid precursors. The available data indicate that use of drugs active in acute myeloid leukemia can improve the prognosis for patients with ETP-ALL. The unique biology of the tumor and the extremely unfavorable prognosis in ETP-ALL necessitate the creation of a new therapeutic strategy for the treatment of this disease. Two clinical case reports of ETP-ALL are presented, demonstrating variants of extremely unfavorable course of the disease and requiring individual therapeutic approaches.