Chromosomal Aberrations in Acute Leukemia

Chromosome studies in acute leukemia were performed in 53 adults and 12 children (two with Down’s syndrome). Abnormalities were encountered in 36 (55.4 per cent) of the cases studied. Normal patterns were found in 29 cases (44.6 per cent). The chromosomal changes varied from patient to patient and consisted of both numerical and structural aberrations. The series involved were, in decreasing order, C, G, D and E, although all chromosomes (autosome and sex) were affected. No correlations of the chromosomal abnormalities with any clinical or hematologic features could be made. In the "blast crisis" of chronic granulocytic leukemia, in addition in Ph 1 chromosome which was present in all cases, other chromosomal anomalies were found in some of these patients.

The presence of normal as well as abnormal chromosomal patterns in acute leukemia, with the great diversity of anomalies in the latter group, suggests that acute leukemia may not be a single entity but comprise instead a variety of morphologic responses to various kinds of etiologic agents.