>

106. Recurrent Infratentorial Ependymomas: A Systematic Review and Meta-Analysis on Outcomes and Molecular Classification

Authors: Eric Montgomery

Introduction:
The prognosis of recurrent ependymomas differs based on location and molecular signature, but the difference in survival of PFA and PFB recurrent ependymomas remains poorly defined in the pediatric population.Methods: We searched PubMed, Scopus, Embase, and Ovid for studies on recurrent infratentorial ependymomas in patients < 25 years old. Exclusion criteria were case series of less than 5 patients and studies that did not provide individualized patient data or averages with sample size and standard deviation/error. Tumors were characterized based on WHO grade and multi-omic molecular classification. Survival was quantified as overall survival after the first recurrence of the primary tumor.
Results:
Our database search yielded 472 unique articles, of which 13 were included in the final analysis. There was a total of 287 recurrent infratentorial pediatric ependymomas reported, with 163 grade II tumors (57.0%) and 123 grade III (43.0%) on histology. One hundred and sixty-one patients were male (56.1%). In the studies that provided molecular classification, there were 109 PFA tumors (90.8%) and 11 PFB (9.2%). The overall mortality for recurrent infratentorial pediatric ependymomas was 58.5% (168/287). Of the studies with individualized molecular data, mortality for recurrent PFA tumors was 44.0% (11/25) and for recurrent PFB tumors 12.5% (1/8). The pooled median survival was 23.53 months after recurrence (95% CI: 11.75-35.31). Ninety-eight patients received initial subtotal resection of the primary tumor (40.7%). Thirty-seven patients received radiation for their recurrence and 30 received chemotherapy. Twenty-one experienced metastasis along with their local recurrence.
Conclusion:
The overall mortality rate of recurrent infratentorial ependymomas was found to be 58.5%, with a pooled median survival of 23.5 months in the sample population. Most of the recurrent infratentorial ependymomas were of the PFA molecular subtype, which also demonstrated a worse survival with recurrence.