Background: Identification of early megakaryocyte (MK) precursors is difficult and conflicting. The prevalence of leukemias with a megakaryocytic component may be underestimated when conventional techniques are utilized. The recent development of immuno-ultrastructural procedures for simultaneous detection of platelet peroxidase reaction and specific platelet membrane antigens has increased our capability of recognizing blast cells of the megakaryocytic lineage.
Methods: In this study the occurrence and distribution of megakaryoblastic in the FAB subtypes of adult "de novo" acute myeloid leukemias was employed to detect megakaryocytic precursors.
Results: A megakaryoblastic proliferation was demonstrated in 8/42 cases (19%), with a much higher percentage than previously reported and an unusual distribution in the M2 subtype.
Conclusions: These findings indicate that megakaryocytic involvement may be found rather frequently when an immunocytochemical ultrastructural method is applied to the characterization of leukemias.