Intracerebral neurinomas in a case of von Recklinghausen's disease (neurofibromatosis).

We report the third case of intracerebral neurinoma in a patient with von Recklinghausen's disease, who died of recurrent subdural hematomas after head injury. A total of ten tumors were found in the brain. Both by histological and ultrastructural standards the multiple tumors resembled neurinomas. The pattern of positivity for S-100 and myelin basic protein indicated the Schwann cell origin of the tumors. The ultrastructural findings indicated Schwann cells and numerous areas showing a well defined basement membrane surrounding spindle-shaped neoplastic cells and other areas lacking basement membrane with Schwann cells embedded in collagen. The present case may be categorized as a mixed form of peripheral and central neurofibromatosis. It seems safe to assume that perivascular nerves are the site of origin of the tumors.