Primary lymphoma of the central nervous system in children with acquired immunodeficiency syndrome.

Three children with acquired immunodeficiency syndrome and primary lymphoma of the CNS are described. All three children had clinical signs of focal mass lesions and progressive neurologic deficits. In one child the deterioration was extremely rapid. New lesions appeared on serial CT scans every few days, simulating an infectious process and leading to death within 3 weeks. Results of neuroradiologic studies in these patients demonstrated multicentric lesions that were often periventricular. On CT scans, the lesions were hyperdense before contrast and were enhanced with contrast medium. Double-dose delayed contrast CT scans and magnetic resonance imaging studies were more sensitive in indicating additional lesions. Histologically, all three tumors were B cell neoplasms; two lymphomas were large cell type, whereas one was small cell, noncleaved (Burkitt-like). Primary CNS lymphoma occurred with an incidence of 1/26 (4%) in our autopsy series and 3/100 (3%) of all pediatric cases of human immunodeficiency virus-type 1 infection, living and dead, that have been seen at the Children's Hospital of New Jersey. By comparison, opportunistic and reactivated latent CNS infections were less common in this same population and never appeared clinically as mass lesions. Therefore, in our experience, primary lymphoma is the most common cause of focal or multifocal mass lesions in the brains of children with acquired immunodeficiency syndrome. This tumor may be radiosensitive. In most cases, early biopsy is probably necessary to establish the diagnosis.