Complete Versus Incomplete Surgical Resection in Intramedullary Ependymomas: A Systematic Review and Meta-analysis

Study Design: Systematic review. Objective: To compare outcomes of complete versus incomplete resection in primary intramedullary spinal cord ependymoma. Methods: A comprehensive search of the MEDLINE, CENTRAL, and Embase databases was conducted by 2 independent investigators. Random-effect meta-analysis and meta-regression with seven covariates were performed to evaluate the reason for the heterogeneity among studies. We also used individual patient data in the integrative analysis to compare complete and incomplete resection based on 4 outcomes: progression-free survival (PFS), overall survival (OS), postoperative neurological improvement (PNI), and follow-up neurological improvement (FNI). Results: A total of 23 studies were identified, including 407 cases. Significant heterogeneity among included studies was observed in risk estimates (I2 for PFS, FNI, and PNI were 49.5%, 78.3%, and 87.2%, respectively). The mean follow-up time across cases was 48.6 ± 2.35 months. Cox proportional multivariable analysis revealed that the complete resection can prolong PFS (model, hazard ratio = 0.18, CI 0.05-0.54, P = .004,) and improve the FNI (binary logistic regression, adjusted odds ratio = 16.5, CI 1.6-171, P = .019). However, PNI and OS were similar in patients with incomplete resected spinal cord ependymoma compared with complete resection (binary logistic regression respectively and Cox multivariable analysis, P > .5). Conclusion: The data presented in this study showed that OS was not significantly affected by the degree of surgery. However, complete resection of intramedullary ependymomas provides the optimal outcomes with longer PFS and better long-term neurological outcomes than incomplete resection.