Primary Non-Hodgkin lymphomas of the central nervous system

Abstract

125 cases of primary Non-Hodgkin’s lymphomas of the brain (104 autopsies, 21 biopsies) were observed among over 10,000 intracranial neoplasms (incidence 1.25%). There was one case of primary lymphoma of the spinal cord. Three patients were immunocomprised. There was a clear male preponderance of 1.6:1. The mean age at diagnosis was 57.5 ± 3.1 years with a range from birth to 89 years. Duration of symptoms ranged from days to 2 years. The most common presenting symptoms were headache, mental status changes, nausea/vomiting, hemiparesis and other focal neurological signs. Elevated CSF protein was the most frequent CSF abnormality. CSF cytology was positive in 45% of the examined cases. CT brain scans showed solitary or multiple enhancing foci. The most common sites of involvement were the cerebral hemispheres (43%), basal ganglia (15%), posterior fossa (12%), corpus callosum (10%), while 20% showed multiple lesions of brain and méninges. Histologically, the most common types according to the Kiel Classification (Lennert 1981) were immunoblastomas (43.2%) and immunocytomas (40.8%), less frequent were lympho-blastomas (12%) and single cases of centroblastoma and unclassified lymphomas. The ultrastructure of primary CNS immunoblastomas and immunocytomas showing transformation of blast cells towards rough E.R. producing plasmablasts with accumulation of immunoglobulines is identical to that of NH lymphomas elsewhere in the body. Immunocytochemistry demonstrating intracytoplasmic monoclonal immunoglobu-lines in both solid tumor and CSF tumor cells indicates that the majority of the primary NH-lymphomas are of B-cell origin. The mean survival without treatment was 1.3 months, after surgery 1.1 months, after radiotherapy (18 cases) 12.2 months, and after combined radio-chemotherapy (34 patients) 17.5 months with poor prognosis of lymphoblastomas and immunoblastomas (mean survival 6.7 and 7.2 months; range 2–24 months, one-year survival 10 and 22%), while immunocytomas had a mean survival of 30.2 months (range 2 to over 240 months) with one-year survival of 75% and two-year life expectacy of 37.5%.