Survival and failure patterns in atypical and anaplastic meningiomas: A single-center experience of surgery and postoperative radiotherapy.

Introduction: Intracranial meningiomas are the second most common tumor of the CNS. The high-grade tumors are atypical and malignant meningioma comprising 5-7% and 1-3% of all meningiomas. The high-grade meningioma have an aggressive histopathological and clinical behavior.
Materials and Methods: We retrospectively reviewed 37 patients of high-grade meningioma treated in our institute from 2002 to 2011. Clinical characteristics and treatment modality in form of surgery and radiotherapy (RT) were noted. Statistical analysis was done with regards to progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier survival analysis.
Results: The median age of the patients was 45.0 years. The median duration of symptoms was 6 months. Headache was the most common presenting symptom. Fourteen patients underwent complete excision, while 23 had subtotal excision. Twenty-two patients had World Health Organization (WHO) grade II histology tumors and 15 patients had grade III histology. Median RT dose delivered was 50 Gy for grade II tumors and 54 Gy for grade III tumors. Five-year PFS for grade II and III tumors was 58 and 20%, respectively. Five-year OS for grade II and III tumors was 83 and 23%, respectively.
Conclusions: High-grade meningiomas represent a rare and aggressive neoplasm. The mainstay of therapy is gross total resection (GTR) at the initial surgery. Postoperative adjuvant RT should be offered to all patients, regardless of the degree of resection achieved. Long-term follow-up is important as local recurrences and progression can develop years after the initial treatment.