PRIMARY LEPTOMENINGEAL LYMPHOMA PRESENTING AS CEREBELLOPONTINE ANGLE LESION

We report a primary leptomeningeal lymphoma (PLML) presenting as a cer ebellopontine angle lesion. CT showed slight enlargement of the ventri cular system, obliteration of the basal cisterns and a dense lesion in the left cerebellopontine angle which enhanced with contrast medium. Cerebrospinal fluid abnormalities included sterile lymphocytic pleocyt osis without malignant cells, low sugar and high adenosine deaminase l evels. An erroneous diagnosis of tuberulous meningitis was made, but a utopsy revealed a leptomeningeal B-cell lymphoma with infiltration of the middle cerebellar peduncle giving the appearance of a cerebellopon tine angle lesion. Seven cases of cerebellopontine angle lymphoma have previously been decribed, only one of which could be classified as PL ML.