The Most Significant Surgical Risk Factors of Giant Intracranial Meningiomas: Localization Matters Much More than Grading and Volume of Peritumoral Brain Edema. A Retrospective Clinical Neuroradiological and Immunohistochemical Study

Giant intracranial meningiomas (GIMs) are a subgroup of meningiomas with huge dimen- sions with a maximum diameter of more than 5 cm. The mechanisms by which a meningioma can grow to be defined as a “giant” are unknown, and the biological, radiological profile and the different outcomes are poorly investigated. We performed a multi-centric retrospective study of a series of sur- gically treated patients suffering from intracranial meningioma. All the patients were assigned on the grounds of the preoperative imaging to giant and medium/large meningioma groups with a cut-off of 5 cm. We investigated whether the presence of large diameter and peritumoral brain edema (PBE) on radiological diagnosis indicates different mortality rates, grading, characteristics, and outcomes in a multi-variate analysis. We found a higher risk of developing complications for GIMs (29.9% versus 14.8%; p < 0.01). The direct proportional relationship between PBE volume and tumor volume was present only in the medium/large group (Pearson correlation with p < 0.01) and not in the GIM group (p = 0.47). In conclusion, GIMs have a higher risk of developing complications in the postoperative phase than medium/large meningioma without higher risk of mortality and recurrence.