The Recurrence Rate in Meningiomas: Analysis of Tumor Location, Histological Grading, and Extent of Resection

Background: Purpose of this study was to evaluate various parameters of meningioma after surgical treatment and analyze predictive factors for recurrence. Methods: During 1992-2007, 353 patients were operated for intracranial meningioma in our department. They were followed since, and related data were combined with parameters such as tumor histology (WHO system), tumor location and the extent of tumor resection (Simpson’s scale). The results were analyzed with respect to tumor reappearance. This study was approved by the ethics committee of G. Papanikolaou Hospital. Results: The mean follow up period was 6.45 years. The overall percentage of recurrence was 21.52%. Grade 1 meningiomas (benign) recurred at a rate of 19.1%, grade 2 tumors (atypical) showed 41.7% rate of recurrence and grade 3 meningiomas (malignant) recurred at a rate of 75%. Tumor histopathology was not significant to recurrence (p > 0.001). The location of meningiomas was not found to be significant to recurrence (p > 0.001). Complete tumor resection was accomplished in 269 patients (76.2%). Incomplete resection (Simpson grades 2-5) took place in 84 cases (23.8%). The recurrence rate after complete resection was 13.8%, while the rate for cases with incomplete resection was 46.7%. The extent of removal was significantly associated with recurrence (p < 0.001). Conclusions: Tumor recurrence was observed at 21.5% of patients in our series of intracranial meningioma surgery. The rate of recurrence was related primarily to the extent of surgical removal. Neither tumor site, nor tumor histology were predictive factors for recurrence (malignant meningiomas excluded).