Longterm meningeal involvement as the only clinical manifestation of low grade malignant non-Hodgkin's lymphoma.

We present the case of a 56-year-old man who developed-at the age of 46-paraesthesia and numbness in the perianal region, the feet and lower legs accompanied by the presence of B-lymphocytes in the cerebrospinal fluid (CSF). Despite intensive work-up an explanation was not found until he developed hepato-splenomegaly ten years after the initial symptoms. Haematologic evaluation at that time disclosed a low-grade malignant B-cell lymphoma. Repeated CSF examination revealed 31 leukocytes/mm3, of which were mainly lymphocytes. These proved to be B-lymphocytes of monoclonal origin. These findings suggest that a leptomeningeal localisation of a low-grade malignant lymphoma had been present for ten years before systemic manifestation of the disease.