Abstract
Chronic myelogenous leukemias have arisen a considerable new interest, since lymphoblastic crises recently turned out to complicate and terminate a primary myeloproliferative disease (Beard et al., 1976; Janossy et al., 1977; Rosenthal et al., 1977). Ways of stem cell differentiation (Metcalf, 1973, 1974, 1977; Boggs, 1974; Moore, 1976; Greenberg, 1976, 1978) as well as biological markers of leukemic cells (Fialkow et al., 1977, 1978a, b) give sufficient proof for the suggestion that hematopoietic stem cells have been primarily involved in this disease.