[Serial spectral EEG analysis in a patient with non-Hodgkin's lymphoma complicated by leukoencephalopathy induced by high-dose methotrexate].

An autopsy case of disseminated necrotizing leukoencephalopathy in non-Hodgkin's lymphoma associated with high-dose methotrexate (HD-MTX) is reported. The patient was a 5-year-old girl, who was admitted to Hamamatsu University School of Medicine because of an abdominal mass in April, 1984. She was diagnosed as having diffuse lymphoma, medium cell type, according to the LSG classification of a biopsied specimen of the liver mass and great omental lymph nodes. Chemotherapy containing HD-MTX was given until the first bone marrow relapse occurred in September, 1985. Subsequently, the physical and CT findings were normal except for decrement of deep tendon reflex, though slight gait disturbance was apparent. In serial spectral EEG analysis, the alpha/s ratio showed slowing activity upon administration of HD-MTX, and it became irreversible. In June, 1986, second bone marrow relapse occurred, and the patient died in July, 1986. At necropsy, multifocal necroses and extensive spongiosis in the white matter of the parietal and occipital lobes were revealed in the bilateral hemispheres of the cerebrum and cerebellum. Irregular confluent demyelination and necroses were also present in the brain stem, especially the pons. Therefore, serial EEG analysis might be a means of achieving early detection of leukoencephalopathy in HD-MTX-treated patients.