Myxopapillary ependymoma: Lesser known cytomorphologic features.

Myxopapillary ependymoma (MPE) is a rare and distinctive tumor which occurs in the sacrococcygeal area of young adults and children, often intradural in location. Histopathologic features have been well-described in the literature whereas cytological findings have been sporadically reported by various authors mainly as case reports. We report the features of a primary sacrococcygeal MPE on aspirate cytology in a 45-year-old female. Cytology smears displayed a papillary pattern with the presence of fibrovascular cores, rimmed by cuboidal to columnar cells sending fibrillary cytoplasmic processes forming pseudorosettes along with the presence of hyaline globules, and myxoid material. Intranuclear inclusions, nuclear grooves, cytologic atypia or mitotic activity was not evident, in this case. MPEs need to be differentiated from the other tumors occurring in this location which may also show myxoid material and papillary fronds. Hence, the recognition of the characteristic cytologic features plays an important role in establishing a preoperative diagnosis.