162 Evaluating Risk of Recurrence in Patients With Meningioma: Analysis of 703 Cases

INTRODUCTION: Meningioma prognostication and treatment continues to evolve with an increasing understanding of tumor biology. METHODS: This is a retrospective study of a consecutive series of patients with WHO grade 1–3 meningioma resected at UT Southwestern from 1994 to 2015. Time to meningioma recurrence (RFS) was the primary endpoint measured. Kaplan-Meier curves were constructed and compared using log-rank tests. Cox univariate and multivariate analyses were performed to identify predictors of RFS. RESULTS: A total of 703 consecutive patients with meningioma underwent resection at UT Southwestern between the years 1994 and 2015. The median age of the cohort was 56 years (range 16-88 years) and was 68.7% (n = 483) female. Median follow-up was 45 months (range 0-289 months). There was not a significantly increased risk of recurrence in patients with evidence of brain invasion, in patients with otherwise WHO grade 1 meningioma (p = .82). Adjuvant radiation to subtotally resected WHO grade 1 meningiomas did not prolong the time to recurrence. Location (midline skull base, lateral skull base, and paravenous) was significantly associated with RFS (p < .01) on univariate analysis. In patients with high grade (WHO grade 2 or 3) meningiomas, location was predictive of RFS (p = .03) with paravenous meningiomas exhibiting the highest rates of recurrence. Location was not significant on multivariate analysis. CONCLUSIONS: Our data suggests that brain invasion does not increase the risk of recurrence in otherwise WHO grade 1 meningioma. Adjuvant radiation to subtotally resected WHO grade 1 meningiomas did not prolong the time to recurrence. Location categorized by distinct molecular signatures did not predict RFS in a multivariate model.