NF2 and spinal meningioma: While 95% of NF2-associated meningiomas remain grade 1 (13), the presence of an NF2 mutation has been associated with increased tumor size and cell proliferation, and it has been suggested that NF2 loss may be the primary and sole initiator of meningioma tumorigenesis in both cranial and spinal meningiomas (16, 17).