Chromosome abnormalities and clinical and morphologic manifestations of chronic myeloid leukemia.

Forty cases of chronic myeloid leukemia (CML) were studied and subgroups of cases with similar chromosomal abnormalities in terminal stage were defined. Certain correlations were observed between the type of chromosomal changes, and clinical and morphologic manifestations of the disease: (1) It seems that, in cases without any karyotype changes other than translocation (9;22), the terminal stage is longer and milder than in cases with additional chromosomal abnormalities; (2) cases with marker i(17q) are clinically and morphologically rather uniform and are characterized by distinct signs of myeloid differentiation of blast cells, absent in other cases; (3) in cases with various atypical chromosomal abnormalities, the course of the terminal stage is the most rapid and grave. The blast cells differ from myeloblasts and resemble lymphoid elements.