Abstract
Tanycytic ependymoma is a very rare spindle-cell variant of ependymoma derived from tanycytes, which are part of the primitive nervous system. This paper is presenting 48-year old woman who presented with low back and right-sided leg pain of moderate intensity. MRI showed spinal intradural tumor at the level of the L1 vertebral body. Right-sided L1 hemilaminectomy and en bloc tumor resection were performed. Neuroradiological and intraoperative diagnosis of schwannoma was revised to tanycytic ependymoma after careful immunohistochemical analysis. Six months post-operativly, MRI did not show tumor recurrence. Tanycytic ependymoma at the region of filum terminale is extremely uncommon and only three cases have been described in the literature. The low incidence of this tumor and atypical histological image, which is distinct from the typical features of commonly encountered ependymomas, can present a challenge in terms of making an accurate diagnosis. Awareness of this transitional form of ependymoma among neurosurgeons and pathologists may avoid incorrect surgical approaches and postoperative treatment course.