FINE-NEEDLE ASPIRATION CYTOLOGY OF MYXOPAPILLARY EPENDYMOMA - A CASE-REPORT

BACKGROUND: Myxopapillary ependymoma is a variant of ependymoma that u sually occurs in the sacrococcygeal region. Histologically, it is char acterized by arborizing papillary fronds of capillaries with mucinous stroma rimmed by ependymal cells. The fine needle aspiration cytology of this rare tumor is rarely described in the literature. CASE: We rep ort the fine needle aspiration cytology of a primary sacrococcygeal my xopapillary ependymoma occurring in a 18-year-old female. Cytology sho wed ''fernlike'' papillae and globules of mucinous and myxoid substanc e containing central capillaries. These structures were rimmed by one to several layers of mitotically inactive, mildly pleomorphic cuboidal to columnar cells with occasional pseudonuclear cytoplasmic inclusion s. Some of these ependymal cells sent fibrillary processes toward the capillaries, suggestive of perivascular pseudorosettes. There were als o numerous isolated tumor cells in the background. CONCLUSION: Because of the prominent mucinous elements and papillary fronds, myxopapillar y ependymoma may mimic other myxoid or papillary tumors cytologically. Recognition of the characteristic cytologic features may allow a dist inction to be made on fine needle aspiration biopsy.