Squash cytology of pleomorphic xanthoastrocytoma mimicking glioblastoma. A case report.
BACKGROUND
Pleomorphic xanthoastrocytoma (PXA) is an uncommon, superficially 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 differentiation from other high grade gliomas is necessary to determine adequate therapy during surgery. Cytomorphologic features of this tumor have been described only rarely.


METHODS
A 22-year-old male had complained of visual disturbance for about a year. Radiologic imaging revealed a well-circumscribed mass with cyst formation in the left temporal area. Squash specimens from fresh tissues were highly cellular. Tumor cells were markedly pleomorphic, with long and coarse cytoplasmic processes showing a fibrillary astrocytic appearance. Pleomorphic cells varied in shape from round to elongated and had large, multilobed, hyperchromatic nuclei but few nuclear mitoses. Sometimes eosinophilic granular bodies were also observed. Blood vessels were found frequently in tumor cell clusters, but their endothelium was not swollen. In the background, considerable leukocytic infiltration, but no cellular debris, was observed. With immunohistochemical studies, most of the tumor cells were positive for glial fibrillary acidic protein and S-100 protein. Some of the mononuclear giant cells were positive for synaptophysin.


CONCLUSIONS
Squash preparations showed the peculiar cytologic features of PXA. Together with the peculiar radiologic findings, the cytologic results make it possible to render a diagnosis of PXA.
Kobayashi
S
S
Department of Pathology, Kagawa Medical University, Kagawa-ken, Japan.
Hirakawa
E
E
Haba
R
R
D000328:Adult; D001254:Astrocytoma / Q000473:pathology*; D001932:Brain Neoplasms / Q000473:pathology*; D003937:Diagnosis, Differential; D005909:Glioblastoma / Q000473:pathology*; D006652:Histological Techniques; D006801:Humans; D007150:Immunohistochemistry; D008297:Male