The Effect of Treatment in Patients with Chronic Myelogenous Leukemia

Abstract

In addlton to the clinical and hematological abnormalities in patients with CML, a low leukocyte alkaline phosphatase (LAP) and a chromosome abnormality of the 21-22 group (Ph1) have been described. Eighty per cent of 32 drug trials in 24 patients with six chemotherapeutic agents resulted in clinical and hematologic improvement. Fourteen of these 24 patients had return of the bone marrow myeloid: erythroid ratio to normal, whereas only 12 patients had a simultaneous return to normal levels of LAP. In no patient did the proportion of Ph1 containing metaphases in the marrow decrease (usually remaining at or near 100 per cent) although the Ph1 containing metaphases in the cultured peripheral blood decreased to less than two per cent when the WBC was less than 10,000. If the Ph1 chromosome marks the leukemic cell, our present methods of chemotherapy do not eradicate the disease. The interrelationships of these cytogenetic and hematologic changes as well as their implications for future therapeutic trials are described.