Retrospective Analysis of 449 Intracranial Meningioma Patients Operated Between 2007 and 2013 at a Single Institute.

AIM: Meningioma literature has many large surgical case series, which have been references of text books and neurosurgical practice. Many of those series were published when stereotactic radiosurgery (SRS) was not so common or these series were in terms of World Health Organization (WHO) 2000 classification. In this study, we aimed to make an update to the current literature using WHO 2007 classification system.

MATERIAL AND METHODS: Four hundred eighty-eight intracranial meningioma patients underwent open surgery in 2007-2013 and 449 of them were included in this study. All pathological specimens were re-evaluated in terms of WHO 2007 classification. All demographical and follow-up records and imaging archives were investigated by using our center"s central automation system and National Central Population Management System. If records were not available or not adequate, investigators made phone calls to patients. Pediatric patients were excluded.

RESULTS: Three hundred twenty-six female (76.2%) and 123 male (27.4%) patients were analyzed. Their ages ranged from 18 to 84 years (mean=51.6±11.9 years). The most common subtype of meningioma was meningothelial meningioma (51.7%), followed by atypical meningioma (20.3%). WHO Grade I meningiomas had statistically random localization distribution, but WHO Grade II meningiomas were more common in the convexity, parasagittal and middle fossa. Younger age was found to be significantly related with tumor recurrence or progression. Seventy-three (16.2%) patients underwent SRS and 64 (14.2%) patients underwent adjuvant radiotherapy (ART) after surgery. Convexity localization was found to be associated with recurrence, mortality and higher WHO 2007 grade.

CONCLUSION: Convexity meningiomas are associated with recurrence, mortality and higher WHO 2007 grade. Convexity meningiomas should be totally resected in order to achieve maximum benefit from surgery.