The Histopathology of Malignant Megakaryocytosis: Report of a Case

A case of malignant megakaryocytosis presenting a blood picture of acute leukemia (50%) blasts), marked hepato-splenomegaly and intense megakaryocytosis and myeloblastosis in the bone marrow, liver and spleen, is described. The authors accept megakaryocytosis as a well-defined disease entity, at least from the viewpoint of pathologic anatomy. The fairly rapid clinical course, the constant hepato-splenomegaly and the characteristic histological picture of the bone marrow, liver and spleen are the essential features necessary for a differential diagnosis from other myeloproliferative syndromes involving the megakaryocytic series.