Ovarian ependymoma

Abstract

A 76-year-old woman presented with a large calcifying mass behind the bladder. The tumor contained solid areas of a yellowish white color. Microscopic examination revealed highly cellular solid areas with many typical ependymal perivascular pseudorosettes. The cells contained uniform round-to-oval nuclei, some of which had irregular contours, clumped chromatin and occasional prominent nucleoli. There was widespread geographic necrosis and there were 5 atypical mitotic figures per 10 high power fields. Glial fibrillary acidic protein (GFAP) immunopositivity was observed in the cytoplasm of the tumor cells. Based on the histopathologic and immunohistochemical features, the tumor was diagnosed as an anaplastic ependymoma. This is to the best of our knowledge only the second case of anaplastic ependymoma in the medical literature.

Supratentorial Extraventricular Anaplastic Ependymoma Presented With Headache in Pregnancy: Case Report and Review of the Literature

“…It has been reported that, from the remnants left in the neural tube, ependymomas may develop in the sacrococcygeal extraspinal region, ovaries, paraovarian tissues, the omentum, the posterior mediastinum, and even in the lungs [18,31]. In the literature, there are very few ovarian ependymoma cases reported [11].…”

“…There is a hypothesis that extraventricular or cortical ependymomas may form from the insertion of an embryonic ependymal tissue remnant into the cerebral cortex during the brain parenchyma's development [7,30]. Within this, it has been reported that, although they generally form in the nervous system, they also very rarely form extracranially [11]. It is thought that extracranial ependymomas grow when the patient is carrying an embryo from remnants in the neural tube or multiply from teratomas [18,31].…”

“…According to the World Health Organization's (WHO) 2007 classification of central nervous system tumors, low-grade ependymoma was grade 2 and anaplastic ependymoma was grade 3 [9,10]. Ependymomas located outside the ventricles are called ectopic, cortical, lobar or extraventricular ependymomas [11,12].…”

Primary pure ependymoma: a rare entity of the ovary

“…In previous reports most patients with early stage received operation only [3,5,8] while patients with advanced stage administrated with adjuvan radiation and/or chemotherapy after cytoreductive surgery [1,3,6,7]. Patients with early stage have longer overall survival with less recurrence rates, so stage seems to be the most important prognostic parameter of survival.…”

“…Ependymal rosettes can be similar to Call-Exner bodies of granulosa cell tumors [4][5][6]. Gland-like areas lined by cells with fibrillary cytoplasmic processes, perivascular pseudorosettes and positive satining for GFAP confirm the diagnosis of ovarian ependymoma [7,8]. Ependymomas can also stain positively for S-100, epithelial membrane antigen (EMA), neuron specific enolase (NSE), cytokeratin, CEA, vimentin, estrogen and progesterone receptors [9,10].…”