Prognostic factors for patients with atypical or malignant meningiomas treated at a single center.

The purpose of this study is to summarize our experience in managing patients with an atypical or malignant meningioma at our institution, with a specific focus on determining the prognostic factors for treatment outcome. We reviewed the records of 126 patients with atypical or malignant meningiomas from January 2001 to August 2011. Data collected included gender, age, Karnofsky Performance Scale (KPS) score, pathology results, cleavability, and bone invasion. The symptoms and signs were recorded for further outcome analysis. There were 37 malignant meningiomas and 89 atypical meningiomas. Total resection (Simpson grade I-II) was achieved in 80.9% of atypical patients (n = 72) and 67.6% of malignant patients (n = 25). Forty patients (44.9%) in the atypical group underwent radiotherapy after surgery, while 26 (70.2%) patients underwent radiotherapy in the malignant group. The median follow-up duration was 25 months. Patients with a secondary tumor had a much shorter progression-free survival (PFS) than those with a primary tumor in the malignant group. The malignant meningioma group had lower overall survival. Progression-free survival for patients in the malignant group who received postoperative radiotherapy was longer than that for those who did not receive radiotherapy. In conclusion, total resection of the tumor was important because patients with a secondary tumor were much more likely to have recurrence than patients with a primary tumor in the atypical and malignant meningioma groups. Also, radiotherapy should be performed after surgery for a malignant meningioma.