A girl with chronic myeloid leukemia received bone marrow transplantat
ion with total body irradiation as part of a conditioning regimen. She
developed leukoencephalopathy about 50 days after transplant. There w
as permanent neurologic impairment afterward. She had not received any
cranial irradiation or intrathecal chemotherapy before transplant. Sh
e had received 10 months of interferon treatment before transplant, wh
ich might have played a part in the development of leukoencephalopathy
.