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Myxopapillary ependymoma (MPE) is a WHO grade I, slow-growing ependymal tumor that arises almost exclusively in the conus medullaris, cauda equina, or filum terminale.
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It is a distinct subtype of spinal ependymoma, characterized by myxoid and papillary histological architecture and is considered benign, though local recurrence and CSF dissemination can occur.
| Feature | Details |
|---|---|
| Age group | Most common in young adults (20–40 years) |
| Sex | Slight male predominance |
| Prevalence | ~13% of all spinal ependymomas; most common tumor of the filum terminale |
Location and Growth Pattern
| Location | Details |
|---|---|
| Filum terminale | Most classic site |
| Conus medullaris & cauda equina | Frequently involved |
| Extramedullary–intradural | Characteristic location (can mimic nerve sheath tumors) |
| Rare sites | Intracranial (fourth ventricle, rare) or intramedullary spread |
Symptoms are usually chronic and slowly progressive
| Symptoms | Mechanism |
|---|---|
| Low back pain | Due to local mass effect |
| Radiculopathy | Sciatica-like pain due to nerve root compression |
| Motor weakness | Lower limb paresis (late) |
| Sensory disturbances | Paresthesia, saddle anesthesia |
| Bladder/bowel dysfunction | Conus/cauda equina involvement |
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"Sausage-shaped" midline tumors in the lumbosacral spinal canal, often near the conus and can be associated with Hemosiderin cap sign and syrinx or reactive enhancement along nerve roots
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MR features:
| MR sequence | Imaging features |
|---|---|
| T1 | • Iso- to hypointense |
| • May show foci of hyperintensity due to mucin or hemorrhage | |
| T2 | • Hyperintense lesion |
| • Well-defined, sausage-shaped or lobulated mass in the filum or cauda equina | |
| • May displace nerve roots | |
| Post-contrast | • Strong, homogeneous enhancement in most cases |
| • May be heterogeneous if hemorrhage or cystic degeneration is present | |
| GRE/SWI | Blooming artifact due to hemosiderin or hemorrhage (seen in ~30%) |
Myxopapillary ependymoma in a fourteen-year-old child located in the lumbo-sacral region. Sagittal T2-weighted (a) and post-contrast T1-weighted (b) images demonstrate solid cranial and caudal enhancing components (blue arrows) and a pseudocystic non-enhancing component (arrowhead). The detail of the filum terminale is also highlighted (white arrow).
Marrazzo A, Cacchione A, Rossi S, Carboni A, Gandolfo C, Carai A, Mastronuzzi A, Colafati GS. Intradural Pediatric Spinal Tumors: An Overview from Imaging to Novel Molecular Findings. Diagnostics. 2021; 11(9):1710. https://doi.org/10.3390/diagnostics11091710
| Differential | Distinguishing Features |
|---|---|
| Schwannoma | Round, eccentric, target sign, often with bony remodeling |
| Meningioma | Dural tail, intense homogeneous enhancement, calcification |
| Drop metastases | Multifocal, enhancing, known primary tumor |
| Paraganglioma | Similar enhancement but more vascular, salt-and-pepper MRI appearance |
| Epidermoid cyst | Non-enhancing, follows CSF signal, diffusion restriction present |