DNA-flow cytometry of blood and bone marrow in chronic myelogenous leukemia

Flow cytometric analysis of bone marrow aspirates and blood samples in 42 patients with chronic myelogenous leukemia (CML) at various disease stages was performed to determine the size of the S-phase compartment of bone marrow and blood. 25 healthy controls were studied for comparative information with both DNA-flow cytometry (DNA-FCM) and 3H-thymidine autoradiography. A correction procedure was applied for peripheral nucleated cell admixture in bone marrow aspirates. The fraction of peripheral nucleated cells in bone marrow aspirates (Fpb) in individual patients was considerable, especially in those with a very high white blood cell count (greater than 100 x 10(9)/l). The size of the S-phase compartments of bone marrow (% Sbm) in patients with CML at diagnosis and in patients at apparent hematological remission was of the same order of magnitude as in normal bone marrow. However, in 3 out of 4 patients at malignant metamorphosis in which the % Sbm could be reliably determined, this percentage was significantly higher than normal (p = 0.013). In 4 out of 11 patients at malignant metamorphosis aneuploidy was noticed. From these findings it is concluded that bone marrow cell proliferation in CML patients at diagnosis and during apparent remission is not essentially different from normal. However, at malignant metamorphosis changes occur in ploidy level and proliferative activity, which can be detected by DNA-FCM already in an early phase.