Primary lymphoma of the brain developing in a boy after a 5-year history of encephalitis: polymerase chain reaction and in situ hybridization analyses for Epstein-Barr virus.

A 7-year-old boy presented with headache, vomiting, fever, epileptic seizure, and a left hemiparesis. Computed tomography revealed low-density areas in the left frontal lobe and right occipital lobe. Incisional biopsy of the right occipital lesion showed a diffuse and laminar destruction accompanied by microglial reaction in the cortex. An encephalitis of unknown etiology was suspected without data on viral titers in the serum and cerebrospinal fluid. Two months later right hemiparesis and ataxia appeared that were alleviated by prednisolone. Thereafter, similar symptoms repeatedly appeared, but disappeared after treatment with prednisolone. Approximately 5 years later, hemiparesis recurred: computed tomography revealed an 8 x 5 cm mass in the right lobe. A brain biopsy revealed non-Hodgkin's lymphoma of diffuse large, predominantly non-cleaved cell type of B-cell nature. The patient died 1 week after the surgery. The first biopsy specimen (taken at 7 years of age) did not contain Epstein-Barr virus genomes even when examined by polymerase chain reaction. The polymerase chain reaction and in situ hybridization techniques on the second biopsy specimens (taken at 12 years of age) revealed the Epstein-Barr virus sequences in the nuclei of diffuse large cell lymphoma. These findings suggested that the Epstein-Barr virus infection occurring between the first and second biopsies played an etiologic role in the pathogenesis of the brain lymphoma.