Neurosurgical Odyssey: Case of Anaplastic Meningiomatosis

According to the World Health Organization grading, meningiomas are classified as grade I (benign), grade II (atypical), and grade III (anaplastic). Most of them (81%) are benign, 15% are atypical, and 4% are anaplastic. Metastasis is a rare event in meningiomas, occurring in <1% of cases. In most types of tumors, distant metastasis is an incontrovertible indication of malignancy. This is not so clearly the case with meningiomas, mostly in the multiple localization of these tumors, known as meningiomatosis. Here we would like to share our experience with a unique case of an atypical meningioma, which evolved in an anaplastic multiple meningiomatosis, invading the brain and associated with a subcutaneous metastasis.