10154-PEDT-6 RETROSPECTIVE STUDY OF 12 PEDIATRIC EPENDYMOMAS TREATED AT OUR HOSPITAL

Abstract

Abstract Ependymoma is an important disease in pediatric brain tumors, but reports with a large number of cases are scarce. In this study, we investigated the clinical course of 12 cases of ependymoma in children treated at our hospital.The median age was 2.5 years (0-15 years), and 10 had posterior fossa and 2 had supratentorial onset. Surgery was performed in all cases, and total resection was achieved in 9 cases (75%). Five cases were diagnosed as ependymoma, Grade II, and seven cases were diagnosed as anaplastic ependymoma, Grade III, according to the WHO revised 4th edition. Adjuvant therapy was administered in 8 patients, 6 with radiotherapy and 2 with combination chemotherapy and radiotherapy. Recurrence was seen in 6 cases, 4 of which were local recurrences and 2 of which were dissemination. The 2-year and 5-year progression-free survival rates were both 60%, and the 2-year and 5-year survival rates were 100% and 66.6%. Progression-free survival/overall survival analysis was performed, and the above results were considered to be equivalent to the published data of 27 cases (Peralia et al. Cell 2022). Progression-free survival tended to be favorable in patients with complete resection (HR = 0.18, 95% CI: 0.025-1.28) and patients with supratentorial disease (HR = 0.18, 95% CI: 0.030-1.11). No difference was seen by WHO grade (HR = 1.022, 95% CI: 0.20-5.24). Our cohort also yielded the same results regarding prognostic factors as previously reported, and WHO grade did not correlate with prognosis. The WHO 5th edition classification adopts molecular diagnosis and further subclassifies ependymoma. Since molecular diagnostics require advanced analytical techniques, there is a problem that it is difficult to put them into practical use, but surrogate markers that can be applied clinically have also been reported. This time, we will reclassify pediatric ependymoma using surrogate markers and compare it with the old classification.