METHOD: We present 45 surgical cases ( 26 atypical and 19 malignant) of total 504 meningiomas operated in Social Security Ankara Education and Research Hospital between 1990-2002. Atypical and malignant meningiomas were diagnosed based on the modified WHO criteria.

RESULTS: Median age of atypical meningiomas was 45.8 with female dominance and of malignant meningiomas was 49.2 years with male predominance. Median survival time of atypical meningiomas for Simpson Grade I was 7.5 years; Grade II was 7.3 years; and Grade III was 7.2 years; while for malignant meningiomas was 7.3, 6.2, 5.6 years, respectively. Median recurrence free interval time was 6.6 years for atypical and 6.5 years for malignant meningiomas. Radiotherapy was performed on two recurred atypical meningiomas and 11 malignant meningiomas.

CONCLUSION: Although malignant meningiomas were accepted to be more aggressive than atypical meningiomas, survival time showed no difference between two groups in our series. Decision making about atypical meningiomas close to malignant forms and radical surgery greatly improved the results in both groups. We also experienced that radiotherapy was beneficial in malignant meningiomas. Keywords : Meningiomas, atypical, malignant, brain neoplasm, recurrence, follow-up, radiotherapy, surgery