Background & objective: New WHO classification has been rapidly used in diagnosis of leukemia. Based on coexpression and correlation of lineage-associated antigens, multiparameter high-resolution flow cytometry has been developed to precisely identify lineage characteristics of leukemia. Some immunophenotypes correlate with cytogenetic abnormality and prognosis. This study was to analyze immunophenotype of naive acute myeloid leukemia (AML), and explore its correlations to cytogenetics, clinical features, and FAB subtype of AML.
Methods: Multiparameter high-resolution flow cytometry with a panel of 25 different monoclonal antibodies was used to analyze the surface and cytoplasmic antigens expressions of 96 adults with AML; G-binding technique was used to analyze karyotype of 73 of the 96 patients.
Results: In these AML patients, some antigens were correlated with FAB subtypes:expression of CD2 was enhanced in AML-M3; HLA-DR, CD34, and CD56 were absent in AML-M3; expression of CD19 was increased in AML-M2; expressions of CD14 and CD56 were enhanced in AML-M5; MPO was absent in AML-M0. Karyotype abnormality was detected in 40(54.8%) patients. CD22, CD56, and TdT expressions were correlated with karyotype abnormality. t(8; 21) was only detected in 10 AML-M2 patients with high expressions of CD15, CD19, CD34, and CD56; no lymphoid lineage antigens were detected in 7 AML-M3 patients with t (15; 17). Expressions of CD4 and TdT were positively correlated with patient's age; expressions of CD7 and CD14 were positively correlated with high white blood cell count; expressions of CD4, CD14, and CD56 were positively correlated with high platelet count.
Conclusions: The abnormal antigen expression of AML is tightly linked with karyotype abnormality. Detection of immunophenotype may help to diagnose and classify AML.