Myxopapillary ependymoma - should we consider earlier intervention for small lumbar intradural tumours? a single-surgeon series.

PURPOSE: Myxopapillary ependymoma (MPE) cannot be reliably distinguished from schwannoma on preoperative MRI in small intradural lumbar lesions. Its 2021 WHO reclassification from Grade I to Grade II reflects recognition of metastatic potential and recurrence risk. This study examines whether these factors support reconsidering the threshold for surgical intervention in small lumbar intradural tumours. MATERIALS AND METHODS: Single-surgeon retrospective review of histologically confirmed MPE at a tertiary neurosurgical centre (2008-2025). Outcomes included extent of resection, perioperative complications, radiological progression, adjuvant therapy, and pre- and post-operative McCormick disability grade. RESULTS: Forty patients (23M:17F; mean age 45.0±17.0 years). GTR achieved in 90%. No patient experienced permanent neurological deterioration; 32.5% improved and 67.5% remained stable. Four patients (10%) progressed radiologically. GTR predicted progression-free survival (χ²=11.62, p=0.0007) but not functional outcome (p=0.40). Seven patients (17.5%) developed metastatic disease; radiological progression occurred in 42.9% of these versus 3.0% of non-metastatic patients. Post-operative radiotherapy was received by 12.5% of patients and was associated with reduced progression-free survival (p=0.015), likely reflecting confounding by indication. CONCLUSION: GTR is the principal determinant of progression-free survival. Given radiological indistinguishability from schwannoma and the 2021 WHO reclassification, these findings support earlier surgical intervention where diagnostic uncertainty exists and GTR is achievable.