Erythroleukemia in a child associated with monosomy 7

A case of erythroleukemia (EL) associated with monosomy 7 is reported. The EL was diagnosed 20 months after the initial diagnosis of monosomy 7 was made. An immunologic study of the blast cells using a monoclonal antibody was positive for glycophorin A, which suggested that they were of erythroid origin; this was confirmed by electron microscopy. Chemotherapy was started with low dose cytarabine. However, the patient had severe bone marrow suppression and died of pneumonia. Our case shows that monosomy 7 is an abnormality of the pluripotential stem cells, including erythroid cells, that resulted in a true erythroid neoplasm.