Cytologic findings in malignant ependymoma: a case report.

BACKGROUND

Intraoperative imprint cytology has proved to be a valuable tool in the diagnosis of central nervous system (CNS) tumors. Ependymomas are uncommon glial neoplasms of the CNS, arising from ependymal lining of the ventricular system and central canal of the spinal cord. Anaplastic ependymoma is a rare tumor that causes diagnostic difficulties in imprint cytology because of variable cytomorphologic findings.

CASE

A 21-year-old girl presented with a history of headache and vomiting. Computed tomography of the head showed hydrocephalus with a large parietal lobe tumor with midline structural shift. Imprint intraoperative cytology revealed a hypercellular smear composed of multiple clusters of small size cells with scant amounts of eosinophilic cytoplasm with high nucleus to cytoplasm ratios. The tumor showed pseudorosettes with glial fibrillary acidic protein and epithelial membrane antigen expression. The diagnosis was made with histologic and immunologic confirmation.

CONCLUSION

Although imprint cytology is a useful method for making a rapid diagnosis, but immunohistochemical markers play a major role in the final diagnosis.