Anaplastic (Malignant) Meningioma

**Semantic type:** Neoplastic Process

**Definition:** A WHO grade 3 meningioma characterized by the presence of malignant morphologic features, including malignant cytology and a very high mitotic index (20 or more mitoses per ten high power fields).

**Synonyms:** - Anaplastic Meningioma - Meningioma, anaplastic