Meningiomas are mostly benign tumors, the majority of which are surgically curable. Some meningiomas have the tendency to recur or to transform to a higher malignant grade with the capacity to metastasize, behaving like sarcomas. Meningiomas are seen at a higher incidence in females. They can cause symptoms related to the nerve origin and by compressing the adjacent brain tissues. The most common of these tumors arise from the vestibular part of the eighth cranial nerve and are called acoustic neuroma.
Neurofibromatosis consists of at least two distinct autosomal dominant hereditary disorders.
NF2 is characterized by bilateral acoustic neuromas and a higher incidence of meningiomas and ependymomas. They are usually benign tumors but can compress the brain and the optic pathway adjacent to the pituitary at the base of the skull. About one half of pituitary tumors produce increased amounts of normal pituitary hormones. Most of this group of tumors originate from displaced embryonic tissue remnants or elements of the pineal gland. This include germ cell tumors, pineocytomas, pineoblastomas and glial derived tumors.