Brain tumors are worrisome and can cause distressing symptoms even when they’re benign from a medical standpoint. For example, one type, called an acoustic neuroma or vestibular schwannoma, is not cancerous but can affect your balance and hearing, causing dizziness and vertigo, tinnitus, and hearing loss. About 3,000 acoustic neuromas are found every year in the United States, though depending on where precisely the tumor is, it may have no noticeable effects on functioning and so go undiagnosed. Neuromas don’t always grow, but if they do it could result in pressure buildup in the skull, causing convulsions and cognitive impairment; in rare cases acoustic neuroma may even be fatal.
Acoustic neuroma can be traced to a flaw in a gene on the 22nd chromosome. The gene, called neurofibramin 2, is ordinarily responsible for directing the production of a protein called merlin that helps build the Schwann cells that form the protective covering around nerve structures. In some people, problems with this gene are hereditary, leading to a condition called neurofibromatosis type 2, which can lead to acoustic neuroma, but in the vast majority of cases there’s no clear cause of the error. People with NF type 2 generally have tumors on both sides of the brain, in the auditory nerves of both ears.
Treatment is available for acoustic neuroma, though it can be dangerous. That’s why it’s important to talk to your health care provider, to figure out what your treatment options are and balance their risks versus the risks of doing nothing. Acoustic neuromas are benign, and the symptoms are the result of pressure on nerves in the brain; if there are no symptoms, there is likely no immediate need to take action, though the patient should be closely monitored.
If treatment is needed, the current options are surgical removal of some or all of the tumor, or a procedure called stereotactic radiosurgery in which gamma radiation is used to stop the tumor’s growth. Radiosurgery is not always effective at preserving hearing. Recently researchers have started studying a possible medication for NF type 2 which would be useful in treating bilateral acoustic neuroma resulting from that condition.