2243 - Long-Term Outcomes and Late Effects of Surgery and Radiotherapy in Adult Spinal and Myxopapillary Ependymoma Patients
Presenter(s)
O. N. van de Langerijt1,2, F. Ehret3,4, A. Niemierko1,5, K. S. Oh1,5, L. F. Borges5,6, J. H. Chi5,6, J. V. C. Coumans5,6, S. Tanguturi1,5, G. R. J. Janssens2, and H. A. Shih1,5; 1Department of Radiation Oncology, Mass General Brigham Cancer Institute, Boston, MA, 2Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, Utrecht, Netherlands, 3Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiation Oncology, Berlin, Germany, 4Department of Radiation Oncology, Mass General Brigham Cancer Institue, Boston, MA, 5Harvard Medical School, Boston, MA, 6Department of Neurosurgery, Mass General Brigham Cancer Institute, Boston, MA
Purpose/Objective(s): Assessment of long-term survival, local control, and radiotherapy-related toxicities in adult spinal ependymoma patients.
Materials/Methods: A retrospective study of adults (=18 years) with spinal intramedullary ependymoma (SIE) or myxopapillary ependymoma (MPE) treated with surgery alone or surgery followed by radiotherapy between 2000-2024 was conducted. Kaplan–Meier analysis and univariable Cox regression were used to evaluate progression-free survival (PFS) and overall survival (OS). Late toxicity was defined as symptoms occurring at least 90 days after radiotherapy initiation.
Results: One hundred six SIE and 81 MPE patients met the inclusion criteria. For SIE, the median follow-up was 5.1 years (interquartile range [IQR] 2.1-10.0). In 88%, a gross total resection (GTR) was achieved, 10% received adjuvant radiotherapy, and 2% experienced recurrence. Five and 10-year PFS were 98% and 96%, respectively; 5 and 10-year OS were 100% and 98%, respectively. GTR, SIE (versus unifocal MPE) histology, and smaller tumor size were significantly associated with improved PFS. The median follow-up for MPE was 3.0 years (IQR 1.1-8.5). Fifteen percent presented with multifocal disease. In the unifocal subgroup, 90% underwent a GTR, 7% a subtotal resection, and 3% a biopsy. Four percent received adjuvant radiotherapy, and 7% experienced recurrence. Five and 10-year PFS for unifocal MPE were 87% and 76%, respectively; 5 and 10-year OS were both 91%. Unifocal (versus multifocal) disease, GTR, lower Charlson Comorbidity Index, and smaller tumor size were significantly associated with improved PFS. In the multifocal subgroup, 60% underwent a GTR of the dominant tumor and 17% of all visible lesions. Fifty percent were treated with adjuvant radiotherapy, and 25% experienced recurrence. Late treatment-related toxicities occurred in 8/18 (44%) SIE and MPE patients with follow-up and were multifactorial in several cases, reflecting effects from underlying disease, surgery, and/or radiation therapy. The most common late grade =2 events were lower limb weakness (17%), upper limb weakness (11%), and ataxia (11%). The only grade 3 toxicity was a sacral bone pathological fracture three years after MPE biopsy, requiring surgical management.
Conclusion: This study affirms the favorable long-term survival and local control rates following surgery, with or without adjuvant radiotherapy, for SIE and MPE, although treatment-related toxicities are not uncommon. Future studies should focus on minimizing treatment-related toxicities.