Recurrent infratentorial ependymomas in children: a meta-analysis on molecular-based outcomes

Abstract The overall prognosis of infratentorial ependymoma differs based on molecular signature, however the impact of recurrence on prognosis remains poorly defined in the pediatric population. PubMed, Scopus, Embase, and Ovid were searched for publications on recurrent infratentorial ependymomas in patients under 25 years of age. Exclusion criteria were case series of less than 5 patients and studies that did not provide individualized patient data. Our search yielded 472 unique articles, of which 17 were included in the analysis. There was a total of 460 recurrent ependymomas reported, with 52.8% WHO grade II tumors and 47.2% grade III. The overall mortality for recurrent infratentorial ependymoma was 49.1% (226/460). The pooled median survival was 32.39 months after recurrence (95% CI: 23.45-41.33). Gross total resection was achieved in 237 (53.1%) patients at initial presentation. Raw mean survival post-recurrence was 32.9 months (SD: 11.2 months) for those who received GTR for their primary tumor versus 23.7 months (SD: 10.8 months) for those who received subtotal resection (STR) (p < 0.001). There was no difference in survival between those that received GTR (49.3 months, 95% CI: 32.3-66.3) versus STR (41.4 months, 95% CI: 11.6-71.2) of their recurrent tumor (p=0.610). In the studies that provided molecular classification, there were 169 PFA tumors (83.3%) and 34 PFB (16.6%), with 28 that demonstrated 1q gain. PFA-A tumors demonstrated worse post-progression survival (24.7 months, 95% CI: 15.3-34.0) compared to PF-B (48.0 months, 95% CI: 32.8-63.2) (p=0.0073). The average post-recurrence survival for tumors with 1q gain was 5.93 months (SD: 9.15). The overall mortality rate for recurrent infrantentorial ependymomas was found to be 49.8%, with a pooled median survival of 32.39 months. Almost 90% of recurrent infratentorial ependymomas were of the PFA molecular subtype, and those tumors that demonstrated 1q gain had a worse survival than those that did not.