The acoustic neuroma is a slowly growing brain tumor, and it develops from and on the nerve sheath of the equilibrium nerve, which, together with the auditory nerve, forms the 8th cranial nerve (vestibulocochlear nerve). «Vestibular schwannoma» is therefore a more specific medical term, while the term cerebellopontine angle tumor is a third synonym for this condition.
Vestibular schwannoma is classified as benign. This means that it will not metastasize to other parts of the body. Despite this, if undetected and untreated, it can sooner or later develop to the point where it involves inconvenient or, later, life-threatening complications.