Squash cytology of pleomorphic xanthoastrocytoma mimicking glioblastoma - A case report

BACKGROUND: Pleomorphic xanthoastrocytoma (PXA) is an uncommon, superficial ly located and well-circumscribed brain tumor that originates in astrocytic cells. Despite the fact that the tumor cells are pleomorphic, with bizarre nuclei, the clinical course is favorable. Cytologic and histologic differe ntiation from other high grade gliomas is necessary to determine adequate t herapy during surgery. Cytomorphologic features of this tumor have been des cribed only rarely. CASE: A 22-year-old male had complained of visual disturbance for about a y ear. Radiologic imaging revealed a well-circumscribed mass with cyst format ion in the left temporal area. Squash specimens from flesh tissues were hig hly cellular. Turner cells were markedly pleomorphic, with long and coarse cytoplasmic processes showing a fibrillary astrocytic appearance. Pleomorph ic cells varied in shape from round to elongated and had large, multilobed, hyperchromatic nuclei but few nuclear mitoses. Sometimes eosinophilic gran ular bodies were also observed. Blood vessels were found frequently in tumo r cell clusters, but their endothelium tons not swollen. In the background, considerable leukocytic infiltration, but no cellular debris, was observed . With immunohistochemical studies, most of the tumor cells were positive f or glial fibrillary acidic protein and S-100 protein. Some of the mononucle ar giant cells were positive for synaptophysin. CONCLUSION Squash preparations showed the peculiar cytologic features of PX A. Together with the peculiar radiologic findings, the cytologic results ma ke if possible to render a diagnosis of PXA.