Chromosome abnormalities in erythroleukemia.

Erythroleukemia (EL) is a heterogeneous disease in terms of cell type affected, chromosome abnormalities found in the malignant clone, and clinical course. In this article, cases of erythroid EL from the recent medical literature are reviewed using cytogenetic criteria to distinguish such cases from those of myeloid EL. Although most patients with erythroid EL were elderly men, 20% of the cases occurred in the under-3 age group, where boys and girls were equally affected. Chromosomes 5 and 7 were found to be lost or partially deleted in two thirds of the adult patients only, but not in the pediatric patients; this suggests that EL is associated with cumulative mutagen exposure in adult patients only. It is proposed that cytogenetic criteria may be of use prospectively in distinguishing patients with erythroid EL from those with myeloid EL.