Megaloblastic changes and chromosome abnormalities of erythropoietic cells in acute myeloid leukaemia

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.