Chronic myelocytic leukemia: cytogenetic findings and their relations to pathogenesis and clinic

The chromosome constitution of myeloid cells of 106 patients with chronic myelocytic leukemia (CML) was studied. Two thirds of the patients were in the chronic and one third in the blastic phase. Particular attention was paid to patients with a mixture of Ph1-positive and Ph1-negative metaphases, and those with additional chromosome anomalies. A statistical analysis of the additional anomalies observed during the chronic and the blastic phase waandom involvement of certain chromosome groups. Chromosomal findings in medullary and extramedullary tissues were compared; the results suggest an accumulation of cells with additional anomalies in extramedullary sites. Ph1-negative patients were shown to be older and to have a survival shorter than Ph1-positive patients. The medium survival time of patients in the blastic phase may be longer in those without additional chromosome anomalies. Apart from the chromosomal status, hemoglobin concentration, the number of platelets and the percentage of myeloblasts in the bone marrow had a definite influence on survival times.