A retrospective analysis of the patterns of failure in pediatric myxopapillary ependymoma

Outcomes following limited-volume proton therapy for multifocal spinal myxopapillary ependymoma

PURPOSE

Spinal myxopapillary ependymoma (MPE) often presents with a multifocal distribution, complicating attempts at resection. There remains no standard approach to irradiating these patients. We report disease control and toxicity in pediatric patients with multifocal spinal MPE treated with limited-volume proton therapy.

MATERIALS/METHODS

Twelve patients (≤21 years old) with multifocal spinal MPE were treated between 2009 and 2018 with limited-volume brain-sparing proton therapy. Median age was 13.5 years (range, 7-21). Radiotherapy was given as adjuvant therapy after primary surgery in five patients (42%) and for recurrence in seven (58%). No patient received prior radiation. Eleven patients (92%) had evidence of gross disease at radiotherapy. Eleven patients received 54 GyRBE; one received 50.4 GyRBE. Treatment toxicity was graded per the CTCAEv4.0. We estimated disease control and survival using the Kaplan-Meier product-limit method.

RESULTS

The median follow-up was 3.6 years (range, 1.8-10.6). The five-year actuarial rates of local control, progression-free survival, and overall survival were 100%, 92%, and 100%, respectively. One patient experienced an out-of-field recurrence in the spine superior to the irradiated region. No patients developed in-field recurrences. Following surgery and irradiation, one patient developed grade three spinal kyphosis and one patient developed grade 2 unilateral L5 neuropathy.

CONCLUSION

54 GyRBE to a limited volume appears effective for disseminated spinal MPE in both the primary and salvage settings, sparing children the toxicity of full craniospinal irradiation. Compared with historical reports, this approach using proton therapy improves the therapeutic ratio, resulting in minimal side effects and high rates of disease control.

Contemporary management of pediatric spinal tumors: a single institute's experience in Taiwan in the modern era

INTRODUCTION

Pediatric spinal tumors are unique pathologies treated by pediatric neurosurgeons. Special attention is required for the preservation of neural function and bony alignment. We reported our experience in the management of these challenging lesions.

METHODS

A total of 75 pediatric patients with spinal tumors treated at the National Taiwan University Hospital from 1998 to 2018 were identified retrospectively. Clinical data, radiographic image, and pathological report were reviewed for analysis.

RESULTS

There were 37 females and 38 males. The median age was 9 years. Thirty-eight tumors (50.6%) were extradural, 20 (26.7%) intradural extramedullary, and 17 (22.6%) intramedullary. The most common pathologies were glioma, ependymoma, and neuroblastoma. The rate of total and subtotal resection was 45.3% and 21.3%. Thirty-four patients (45.3%) required post-operative adjuvant therapy. Eight patients (10.6%) with spinal deformity had simultaneous tumor excision and spinal fusion surgery. Additional six (8%) patients had subsequent spinal fixation and fusion for deformity after primary tumor operation. Eighty-four percent of patients were ambulatory 3 years after operation. For patients with intradural extramedullary and intramedullary tumors, worse survival outcome was associated with tumor derived from CSF seeding and cranial involvement of spinal tumor, while poorer functional outcome was correlated with cranial involvement and adjuvant therapy with chemotherapy or radiotherapy.

CONCLUSIONS

Pediatric spinal tumor surgery carries low surgical morbidity and mortality under current standard of neurosurgical practice. Post-operative adjuvant therapy is required for nearly half of the cases. Spinal deformity requires special attention and sometimes surgical correction. Contemporary management of pediatric spinal tumors enables effective ablation of the lesion and delivers favorable outcome for the majority of patients.