NCI Definition: A WHO grade II meningioma characterized by the presence of brain invasion and an increased mitotic activity, or at least three of the following morphologic features: small cells, high cellularity, prominent nucleoli, lack of architectural pattern, and necrosis. 
Atypical meningiomas most frequently harbor alterations in NF2, CDKN2A, SMO, ROS1, and PTEN .
NF2fs, NF2 Mutation, NF2 Nonsense, CDKN2A Loss, and SMO Mutation are the most common alterations in atypical meningioma .
There is 1 clinical trial for atypical meningioma, of which 1 is open and 0 are completed or closed. Of the trial that contains atypical meningioma as an inclusion criterion, 1 is phase 2 (1 open).
Nivolumab is the most common intervention in atypical meningioma clinical trials.
Significant Genes in Atypical Meningioma
H3F3A is an inclusion eligibility criterion in 1 clinical trial for atypical meningioma, of which 1 is open and 0 are closed. Of the trial that contains H3F3A status and atypical meningioma as inclusion criteria, 1 is phase 2 (1 open) .
2. The AACR Project GENIE Consortium. AACR Project GENIE: powering precision medicine through an international consortium. Cancer Discovery. 2017;7(8):818-831. Dataset Version 8. This dataset does not represent the totality of the genetic landscape; see paper for more information.