central nervous system involvement at presentation in the chronic phase of chronic myelogenous leukemia in childhood with the advent of more effective chemotherapy an increasing incidence of central nervous system involvement in acute lymphocyte all and myelocytic leukemias aml and chronic myelocytic leukemia cml in blast crisis has become evident meningeal involvement in the chronic phase of cml is rare we report two children whose initial presentation of ph1 cml was in the central nervous system as documented by cytocentrifugation aggressive combination chemotherapy and cranial irradiation has resulted in prolonged survival without blastic transformation or further meningeal disease an approach to children with cml is suggested