The causes of<unk> ta are not well understood. Most cases are sporadic, appearing randomly, while some are familial. Persons who have undergone radiation, especially to the scalp, are more at risk for developing<unk> ta, as are those who have had a brain injury. Atomic bomb survivors from Hiroshima had a higher than typical frequency of developing<unk> ta, with the incidence increasing the closer that they were to the site of the explosion. Dental X-rays are correlated with an increased risk of<unk> , in particular for people who had frequent dental X-rays in the past, when the X-ray dose of a dental X-ray was higher than in the present. Having excess body fat increases the risk. A 2012 review found that mobile telephone use was unrelated to<unk> . People with neurofibromatosis type 2 (NF-2) have a 50% chance of developing one or more<unk> ta. Ninety-two percent of<unk> ta are benign. Eight percent are either atypical or malignant. Genetics The most frequent genetic mutations (~50%) involved in<unk> ta are inactivation mutations in the neurofibromatosis 2 gene (merlin) on chromosome 22q. TRAF7 mutations are present in about one-fourth of<unk> ta. Mutations in the TRAF7, KLF4, AKT1, and SMO genes are commonly expressed in benign skull-base<unk> ta. Mutations in NF2 are commonly expressed in<unk> ta located in the cerebral and cerebellar hemispheres.
Meningioma
Metastasis
Glioma
Solitary fibrous tumor
Hemangioblastoma
Lymphoma
Astrocytoma
Schwannoma