RARE-03. EPENDYMOMAS ARISING OUTSIDE OF THE CENTRAL NERVOUS SYSTEM: A CASE SERIES

Extracranial and extraspinal ependymomas are extremely rare tumors mostly published in the literature as case reports. METHODS: Our institutional database was screened for patients with extra CNS ependymomas over a 25 year period. RESULTS: Eight patients with extra CNS ependymoma were identified. Five cases originated in the sacrum or subcutaneous sacral area, and the other 3 cases originating in the breast, lung and adnexa of the uterus. By histology, most cases were myxopapilary ependymomas (5 cases), 2 cases were grade 2 ependymoma and 1 case was an anaplastic ependymoma. Metastases occurred in 6 cases and 3 patients died due to progressive disease. Most cases required surgery, radiation and chemotherapy. CONCLUSION: Extra CNS ependymomas are very rare tumors that tend to metastasize, even though most cases are histologically classified as low grade ependymomas, suggesting that the tumor biology does not correlate with conventional histologic findings. Future plans include molecular phenotyping to determine if these rare cancers are molecular similar to the recent findings from infratentorial, supratentorial ependymomas or the metabolic profile of classic spinal myxopapillary ependymoma.