However, specific immunocytological markers for primary peripheral PNET are HIC-2 gene (CD 99),[8] NSE and synaptophysin and glial fibrillary acidic protein (GFAP).[9] The first two cytological markers were positive in our case, thus confirming the diagnosis of primitive neuroectodermal tumor. The gene discussed is GFAP; the disease is primitive neuroectodermal tumor.