Role of glial fibrillary acidic protein (GFAP) marker in central nervous system lesions

Introduction: The subject of tumours of the nervous system is often looked upon with apprehension by medical practitioners as central nervous system tumours constitute 1-2% of all the neoplasms. Gliomas constitute 38.7% of CNS tumours in which high grade gliomas are 59.5% of patients with systemic malignancies develop brain metastasis during their disease. Glial fibrillary protein is the most frequently used marker in diagnostic neuro-oncology. Positive reaction to GFAP has been demonstrated in astrocytomas, ependymoma and astrocytic cells of mixed gliomas, subependymal giant cell astrocytoma, pleomorphic xanthoastrocytoma, astroblastoma and gliosarcoma. Aim of the study: In the present study the main aim is to differentiate glial tumours from other lesions by morphology and confirmation by using Glial Fibrillary Acidic Protein (GFAP) immunostaining. Results: In the present study glial tumors formed the largest group of cases (44 cases; 41.9%) diagnosed on cytology. They were further divided into low grade and high grade glioma / astrocytoma (33 cases, 31.4%), oligodendroglioma (1 case, 0.95%) and ependymoma (7 cases, 6.6%) based on cytological features. Subsequently, as shown in table IX, the cytohistopathological correlation for glioma / astrocytoma was 91.6%. There were 10 cases which turned out to be oligodendroglioma (4 cases, 11.1%), ependymoma (4 cases, 11.1%) and ganglioglioma (2 cases, 6.0%). Keywords: GFAP, Glial Fibrillary Protein, Astrocytomas, Ependymoma