Abstract: The purpose of this study was to assess the possible relationship
between the cytochemical enzyme profile and
immunophenotypic characteristics of distinct acute myeloid
leukemia (AML) subtypes in discrete stages of leukemic cells
maturation. As the proportion of leukemic blast cells is critical
for exact cytochemical analysis, study was restricted to the
evaluation of 48 adult and pediatric patients with newly diagnosed
AMLs with 80% or more blasts in analyzed samples. The
cytochemical investigation of myeloperoxidase (MPO), Sudan black B
(SBB), chloroacetate esterase (CAE), alpha-naphthyl
butyrate esterase (ANBE), alpha-naphthyl acetate esterase (ANAE) and
acid phosphatase (AP) in peripheral blood and/or bone
marrow was performed. The immunophenotype was examined for the
maturation dependent myeloid antigens CD13,
CD33, CD11b, CD14, CD15, CD65, CD36, cytoplasmic MPO, non-lineage
associated CD34 and HLA-DR antigens, lymphoid-
associated antigens CD7, CD4, CD38 as well as natural killer cell
associated marker CD56. Flow cytometry by double
marker staining and visualization of pathologic cells in dot plots
reflected immunophenotypic aberrancy and degree of
cell maturation. The patients were classified into AML subtypes M0-
M2, M3, M4 and M5 according to the main morphological,
cytochemical and immunophenotypical features. The variable
combinations of MPO, SBB, CAE and ANBE were
identified in relation to immunophenotype. The cytochemical
profile of blasts was in concordance with immunophenotype,
particularly in more differentiated AML subtypes, M3, M4 and M5.
The findings of myeloid antigens expression and
cytochemical features in poorly differentiated AML subtypes showed
no practical relevance of cytochemical analysis. Notwithstanding
that the cytochemical analysis of AML subtypes not sufficiently
identifies the distinct aberrancies in heterogeneous
leukemic blast cell populations, evaluation of the cytochemical
profile in connection with immunophenotyping may
help to classify the AML patients to relevant subtypes with more
accuracy.
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