Immunohistochemistry can be used to subtype acute myeloid leukemia in routinely processed bone marrow biopsy specimens - Comparison with flow cytometry

Flow cytometry (FC) is the preferred method of immunophenotyping acute myel oid leukemia (AML). However; there are situations in which FC is unavailabl e and in which immunohistologic staining of bone marrow biopsy specimens ca n be used to provide immunophenotypic information. To evaluate immunohistol ogic staining and to confirm its value, we selected 80 newly diagnosed case s of AmL that were classified according to French-American-British (FAB) cr iteria and confirmed by flow cytometric analysis for this study. Paraffin-e mbedded bone marrow specimens were stained using a panel of antibodies that included CD34 (QBEND10), antimyeloperoxidase (anti-MPO), antihemoglobin, f actor VIII-related antigen, and 3 epitopes of CD 68 (HAM56, KP1, and PG-M1) . Our findings suggest that with the use of the paraffin reactive antibodie s CD34 (QBEND10), MPO, CD68 (PG-M1), antihemoglobin, and factor VIII-relate d antigen, immunohistochemistry can be used to subclassify AML. Comparison of immunohistochemical results with FC immunophenotyping suggests that ther e is significant concordance in the results for markers that can he used wi th both techniques, indicating that the sensitivity and specificity of both methods is comparable (P > .53 in all cases).