Bone marrow dysfunctions preceding acute leukemia in children: a clinical study

This is a review of preleukaemic states in children. In a prospective series of 109 children with AML the overt disease was preceded by MDS in 22 cases. Ten of these patients had Down's syndrome. Advanced FAB groups were represented in the series. An important subgroup is the bone marrow monosomy 7 syndrome. Cytogenetic anomalies are common in MDS, and multiple and complicated abnormalities develop in nearly all patients with progressing disease. Some children die before transformation to overt ANLL. Transformation usually occurs, few children survive. With cytostatic treatment the risk of irreversible aplasia is great. The choice of schedule should therefore be carefully considered. Bone marrow transplantation has proved beneficial in a number of cases, but these are still quite few. The dysfunction of the bone marrow preceding ALL is due to transient aplastic anaemia--spontaneous remission--overt ALL, often FAB type L1, immunophenotype CALLA. The ALL reacts to the same treatment as de novo ALL of the same type and the prognosis is the same.