Myxopapillary ependymoma of the conus medullaris and filum terminale in the pediatric age group.

Myxopapillary ependymoma of the conus medullaris and filum terminale is a relatively common spinal intradural neoplasm in adulthood. However, only a reported 8-12% of such tumors affect this site in children, and the ideal management remains controversial. Three children with myxopapillary ependymomas of the conus medullaris and filum terminale were treated by the author over a 2-year period with an at least 24-month follow-up. These children, ages 7, 8 and 13 years, included 1 male and 2 females. Their salient presentation was an acute exacerbation of chronic lower back pain. The duration of symptoms prior to diagnosis ranged from 16 to 18 months. A preoperative MRI, with and without contrast, was available for every case. All children underwent replacement laminoplasty with gross total tumor resection. Somatosensory evoked potentials were used in all surgeries. An early postoperative MRI of the entire neural axis was available for all cases. No permanent complications were noted. Self-catheterization for 6 weeks was required in 1 child with preoperative urinary incontinence. One child received radiation therapy following a recurrence. Clinical and surgical results were compared to the only 2 other reported series (11 patients) addressing this type of tumor in children. Based on this review, the authors propose that: (1) unexplained and intractable lumbar pain in childhood should be thoroughly investigated with an MRI scan: (2) the gross feature of myxopapillary ependymoma allowing for complete resectability appears to be the key prognostic factor; (3) radiotherapy appeared to have no proven value in completely resected tumors in children; (4) postoperative baseline MRI and regular sequential imaging studies are essential for long-term follow-up, and (5) replacement laminoplasties may be of value in preventing future spinal deformities, musculoskeletal pain and allowing for an 'easier' resection in the event of a recurrence.