Neurologic manifestations of intravascular lymphomatosis.

Intravascular lymphomatosis is a rare fatal neoplasm characterized by malignant cells of lymphocytic lineage producing vascular occlusions. The cerebral vasculature is particularly affected. Two patients seen at our institution presented with progressive neurologic deficits including dementia, hemiparesis and myelopathy. Review of an additional 64 reported cases with neurologic involvement indicates that patients developed intermittent fevers, an encephalopathy ranging from acute disorientation to rapidly progressive dementia, and focal signs such as hemiparesis and myelopathy. Common laboratory abnormalities include elevated cerebrospinal fluid protein and a lymphocytic pleocytosis, elevated blood erythrocyte sedimentation rate and serum lactate dehydrogenase. Malignant cells are rarely seen in cerebrospinal fluid, blood or bone marrow. Neuroimaging is usually abnormal with parenchymal lesions seen on cerebral tomography and magnetic resonance imaging along with an occasional meningeal pattern of contrast enhancement. Treatment with corticosteroids, chemotherapy, radiation therapy, or plasmapheresis provided limited benefit. Intravascular lymphomatosis should be considered in the differential diagnosis of unexplained progressive encephalopathy with superimposed focal deficits.