Two Leukemic Peripheral Blood Stemlines During Acute Transformation of Chronic Myelogenous Leukemia in a D/D Translocation Carrier

Abstract

Two characteristic malignant cell lines were consistently found in each of two different studies performed at a three month interval in a 53-year-old white female with acute blastic transformation of chronic myelogenous leukemia. One stemline included the Philadelphia (Ph1) chromosome; the other, probably derived from the former, showed in addition replacement of an E17 member by an abnormal chromosome. This marker (M) had symmetrical limbs, each the length of the long arm of the single E17 identified in these cells. Both leukemic stemlines also carried a D/D translocation similarly present in cells derived from skin cultures. A tentative interpretation was the following: D/D translocation = congenital; D/D translocation + marker Ph1 = chronic myelogenous leukemia; D/D translocation + Ph1 + marker M replacing one E17 (? isochromosome for long arm of E17) = acute transformation of the chronic myelogenous leukemia, the final step being regarded as speculative.