Myxopapillary ependymoma with interval postoperative CSF seeding: A report of an unusual case.

Myxopapillary ependymoma (MPE) is a unique slow-growing benign (WHO grade 1) subtype of spinal cord ependymoma arising predominantly in the filum terminale. Despite its benign nature, it occasionally disseminates through the cerebrospinal fluid and metastasizes to distant sites. Here, we report an extremely rare case of MPE with interval CSF seeding and metachronous metastasis in a 47 -year-old female presented as a gradually increasing low back pain for three months with bilateral radiculopathy down to the knees. Magnetic resonance imaging (MRI) showed an intradural extramedullary spinal mass of iso-intense signal to the cord on T1 weighted-images (WIs), heterogeneous, predominantly hyperintense signal on T2WIs with homogenous enhancement after contrast administration. L2 laminectomy with gross total resection (GTR) was performed, and histopathological results confirmed the diagnosis of MPE. Adjuvant radiotherapy was administered, followed by series of MRI scans. 28 months after GTR, Lumbar MRI showed multiple tiny enhancing nodules in the cauda equina. 44 months follow-up whole spine MRI revealed multiple intradural extramedullary nodules throughout the entire spine. The largest one measures about 1.5cm opposite to T3 -T4 intervertebral disc space. The patient underwent T3 and T4 laminectomy and GTR under general anesthesia using microsurgical techniques, and the histopathological result came with the diagnosis of MPE.