Primary ependymoma of the ovary: a case report and literature review.

Ependymoma is a glioma with differentiation toward ependymal cells that usually arises in the central nervous system. Ovarian ependymoma is extremely rare, and the treatment strategies for this disease have not been established. This is the first report of a patient with advanced ovarian ependymoma who received fertility-sparing surgery and is now alive without disease. A 23-year-old Japanese woman, gravida 0, presented with a chief complaint of lower abdominal distension and weight loss. She underwent left salpingo-oophorectomy for suspected ovarian cancer. Microscopic examination revealed a highly cellular tumor composed of small cells with hyperchromatic, round-to-oval nuclei and scanty cytoplasm. Perivascular pseudorosettes, ependymal rosettes, and extensive necrosis were observed. After thorough pathologic examination, she was diagnosed as having stage IIIC ovarian ependymoma. Postoperatively, she received adjuvant chemotherapy and underwent secondary cytoreductive surgery that preserved the uterus and right ovary. Her menstrual cycle has resumed, and she is alive without evidence of disease 16 months after the start of treatment. Although rare, primary ovarian ependymoma must be kept in mind in the differential diagnosis of ovarian tumors, especially in young women. Administration of etoposide-based chemotherapy along with cytoreductive surgery is a potential standard treatment for advanced ovarian ependymoma.