Additionally, PTEN mutations were found to be more frequently associated with a WHO grade 3 (n = 15/176, 8.5%) than grade 2 (n = 17/441, 3.8%, p = 0.025) or grade 1 (5/220, 2.3%, p = 0.0094) meningioma in our cohort. This evidence concerns the gene PTEN and meningioma.