Enzyme markers in acute leukemias: advances during the last decade.

Besides the recent advances in immunology that provided important information for the characterization of leukemia cells, enzyme marker analysis is another area of progress in leukemia research. Assays of enzyme activities, both quantitative enzyme levels and qualitative isozyme changes, are of value in the classification of leukemias. The interest in the study of enzyme markers is due not only to technical improvements and new biochemical possibilities, but also to the involvement of enzyme marker analysis in the so-called "multiple marker analysis," which combines traditional and recently developed techniques in leukemia research. The aims of this review are to describe well-known and potential enzyme markers as well as to stress the relevance of enzyme marker analysis combined with multiple marker analysis for leukemia subclassification and the understanding of normal hematopoietic cell differentiation.