Outcome and survival following primary and repeat surgery for World Health Organization Grade III meningiomas.

OBJECT Despite an increased understanding of the biology of malignant meningioma tumor progression, there is a paucity of published clinical data on factors affecting outcomes following treatment for these lesions. The authors present the largest case series to date dealing with these tumors, providing analysis of 63 patients. METHODS The authors identified all patients undergoing resection of WHO Grade III tumors at their institution over a 16-year period. They analyzed clinical data from these patients, and performed Kaplan-Meier and Cox regression analyses to determine the impact of different clinical characteristics and different treatment modalities on survival following initial and repeat surgery for these lesions. RESULTS Sixty-three patients met inclusion criteria and were analyzed further. The median clinical follow-up time was 5 years (range 1-22 years). The 2-, 5-, and 10-year overall survival rates following initial operation were 82, 61, and 40%, respectively. Kaplan-Meier analysis demonstrated a marked survival benefit with repeat operation (53 vs 25 months, p = 0.02). Interestingly, patients treated with near-total resection experienced improved overall survival when compared with patients treated with gross-total resection at initial (p = 0.035) and repeat operations (p = 0.005). Twelve (19%) of 63 patients experienced significant neurological morbidity referable to the resection of their tumors. CONCLUSIONS Surgery is an effective treatment for WHO Grade III meningiomas at presentation and recurrence; however, aggressive attempts to achieve gross-total resection can be associated with significant neurological risk.