Thoracic Intradural Extramedullary Ependymoma with Anaplastic Transformation: Case Report and Discussion

Intradural extramedullary spinal ependymomas arising from outside the region of the conus medullaris are rare clinical entities, and anaplastic transformation of these lesions is even more exceptional.

We report on a case of an intradural extramedullary T5-T6 ependymoma that underwent gross total resection. Histologic analysis of the initial tumor revealed a World Health Organization grade 2 ependymoma. Two years after initial surgical resection, there was radiologic recurrence and a re-do resection was performed with subsequent spinal stabilization. Histologic analysis of the recurrent tumor revealed a World Health Organization grade 3 ependymoma. After surgery the patient received radiotherapy, and he remains disease free at 2 years following his second surgery. In addition, we employed carbon fiber screws and rods for stabilization in his second operation to reduce artefact on follow-up imaging.

We advocate that primary spinal ependymomas should be within the differential of intradural extramedullary lesions arising outside the region of the conus medullaris.