Involvement of the central nervous system in non-Hodgkin's lymphoma.

Fifteen of 146 (10%) adult patients with non-Hodgkin's lymphoma showed clinical and pathologic evidence of involvement of the central nervous system (CNS): in 6 patients, the CNS lymphoma was present at the onset of disease, in 3 of them it was the only sign detected. In the remaining 9 cases, CNS involvement appeared during the course of systemic disease. In all cases symptoms related to infiltration of the CNS were associated with advanced disease (stage IV); bone marrow or bone involvement was found in 9 patients (60%). The histologic subtypes were mostly of high-grade malignancy according to the Kiel classification: immunoblastic (3), centroblastic (3), Burkitt type (2), lymphoblastic (1), LP immunocytoma in polymorphic variant (3), unclassifiable (3). The prominent signs and symptoms of CNS lymphoma are listed: the cranial nerve palsies are the most common finding. The principal means of detecting CNS involvement are discussed: cerebrospinal fluid cytology, brain scan and CAT scan were the most useful diagnostic procedures. The reported data allow identification of patients at high risk of CNS lymphoma: this includes histologies of high-grade malignancy, advanced stage of disease, and bone marrow or bone infiltration. Therefore, either intensive systemic chemotherapy or CNS prophylaxis are recommended for patients with high risk of CNS disease.