PRIMARY DIFFUSE LEPTOMENINGEAL GLIOMATOSIS (PDLG) - A NEOPLASTIC CAUSE OF CHRONIC MENINGITIS

Cancerous 'chronic meningitis' may be related to subarachnoid space in volvement by solid tumors, hematologic malignancies or rarely intrapar enchymatous gliomas. Primary leptomeningeal gliomatosis is a rare cond ition that is attributed to malignant transformation of heterotopic ne uroglial tissue. We discuss the clinical and biological features of a patient who died with the diffuse form of primary leptomeningeal gliom atosis (PDLG). A literature search shows that a one to two months long non-specific prodromal phase followed by a fluctuating neurologic dow nhill course is suggestive of this disease. Cerebro-spinal fluid (CSF) cytology has been diagnostic in only 1 of 8 reported cases. Recent te chnical progress, including the use of GFAP (glial fibrillary acidic p rotein) directed antibody, may enhance the sensitivity of CSF cytologi es. Diagnosis may require repeated cerebral biopsies, because the hemi spheric lesions are often separated by normal tissue. PDLG must be add ed to the large differential diagnosis of 'chronic meningitis'.