Megaloblastic Changes and Chromosome Abnormalities of Erythropoietic Cells in Acute Myeloid Leukaemia

Abstract

Using Giemsa banding technique, the bone marrow chromosomes were studied in 9 patients with acute myeloid leukaemia (AML). Four patients had 100% normal diploid cells and 5 had 100% abnormal cells; 28–92% of the mitoses were found in erythroid cells. The percentage of erythroblasts with megaloblastoid changes was abnormally high. It was not increased in the cases with chromosomal abnormalities. These findings indicate that chromosomal aberrations are not prerequisites for the development of megaloblasts in AML. Furthermore, abnormalities in the DNA synthesis bringing about the megaloblastoid changes may occur without influencing karyotype.

Isochromosome 17 in a Case of Eosinophilic Leukaemia

“…Current evidence strongly indicates that CML is a clonal disease of a multipotent haematopoietic stem cell (Boggs 1974). Also in acute leukaemia evidence has accumulated that not only the myeloid series but also erythroblasts (Krogh Jensen & Killmann 1967, 1971, Brandt et a1 1974b, 1975, Blackstock & Garson 1974, monocytic precursors (Brandt et al 1974a) and megakaryocytes (Brandt et al 1974b) are involved in the leukaemic process suggesting a common stem cell abnormality. The present case adds some further information on this issue.…”