Long-Term Surgical Resection Outcomes of Pediatric Myxopapillary Ependymoma: Experience of Two Centers and Brief Literature Review

BACKGROUND: Myxopapillary ependymoma (MPE) is a rarely reported lesion of the spinal cord in the pediatric population. Based on their low mitotic index and slow-growth, MPEs are classified as low-grade glial tumors. However, MPEs have malignant characteristics, such as distant neural axis and extraneural axis dissemination. We present the long-term surgical resection outcomes of 5 consecutive pediatric MPE cases and the results of a literature search for reported cases of pediatric spinal MPE. METHODS: We retrospectively reviewed the medical records of 38 primary spinal MPE cases who underwent surgery at 2 neurosurgical centers over a 16-year period from January 2004 to January 2019. All pediatric cases (age <18 years; n = 5) who were diagnosed with MPE composed the core sample for this study. RESULTS: This series comprised 5 patients (3 females and 2 males), with a mean age at first presentation of 13.6 +/- 2.3 years. The mean preoperative course was 8.2 +/- 9.3 months. The predominant location was the lumbar spine, for 4 tumors. Gross total resection (GTR) was achieved in 4 patients. All patients were diagnosed histopathologically as MPE, World Health Organization grade I. No adjuvant treatment was provided after the first surgery. Three patients experienced spinal drop metastasis. The mean interval between the first diagnosis and diagnosis of neural dissemination was 44.0 +/- 31.5 months. The location of neural dissemination in all patients was the sacral spine; 1 patient experienced distant metastasis in the brain along with her sacral metastasis. The mean duration of follow-up was 75.0 +/- 37.6 months. CONCLUSIONS: Even with GTR, pediatric MPE has a high propensity for neural axis dissemination. We recommend close clinical and radiologic follow-up for pediatric patients with MPE.