RESTORATION OF NON-CLONAL HEMATOPOIESIS IN CHRONIC MYELOGENOUS LEUKEMIA (CML) FOLLOWING A CHEMOTHERAPY-INDUCED LOSS OF THE PH1 CHROMOSOME

  • 1 January 1980
    • journal article
    • research article
    • Vol. 56  (3) , 356-360
Abstract
After intensive chemotherapy [thiotepa, daunorubicin , cytosine arabinose, 6-thioguanine], marrow cells of some patients with Philadelphia chromosome (Ph1) positive chronic myelogenous leukemia (CML) become partially or completely Ph1-negative. Without a 2nd marker for the neoplastic clone, it could not be determined if these Ph1-negative cells arose from normal progenitors or were still members of an abnormal clone. A patient with Ph1-positive CML, also heterozygous for glucose-6-phosphate dehydrogenase (G6PD), was studied before and after intensive chemotherapy. Prior to treatment only G6PD type B was detected in the patients''s red cells, platelets and granulocytes, all unstimulated marrow metaphases had Ph1. After 4 cycles of chemotherapy, 76% of marrow cells were Ph1-negative; approximately 80% of the granulocytes were nonclonal by G6PD analysis. The frequency of nonclonal cells by G6PD analysis correlated closely with that of the PH1-negative cells. Intensive chemotherapy apparently can restore nonclonal and presumably non-neoplastic hematopoiesis in CML.