When people hear the words “brain tumor” they automatically think cancer. Fortunately, brain tumors of any kind are relatively rare, and many are benign.
Even benign tumors can still cause health issues if they become large enough to press on the brain or on nerves leading to the brain. Fortunately, non-cancerous tumors tend to grow quite slowly, and in some cases are best left untreated as long as they do not cause problems.
The most common type of benign brain tumor is an acoustic neuroma (AN). It grows deep inside the skull near the brain stem. Although actually located outside of the brain itself, it presses against the brain and nerves. It is non-invasive, meaning it will not penetrate the brain itself, and it will not spread to other locations. Acoustic neuromas are found in all races and, in most cases, they are not hereditary, relatively uncommon.
Common symptoms can include loss of balance and constant ringing noises in one ear. A large tumor may cause facial twitching, headaches and lack of sensation in parts of the face on the same side as the tumor. These problems are caused by the tumor pressing on cranial nerves that carry signals to and from the brain. Some patients, especially with a small tumor, may not experience any symptoms at all, and only discover they have an AN when an MRI (Magnetic Resonance Imagery) or CT (computerized tomography) scan done for some other reason, such as a head injury or headaches, reveals the tumor’s existence. And the symptoms vary based on the size and location of the tumor.
Unilateral hearing loss is a frequent indicator of an AN, and results from the tumor blocking the acoustic nerve, preventing sounds from being carried from the inner ear to the brain. Since the nerve is blocked, a conventional hearing aid is ineffective. An acoustic neuroma often is diagnosed only after a patient develops unexplained and occasionally sudden hearing loss in just one ear. Other less common symptoms include dizziness, headache, nausea vomiting, sleepiness, vision problems.
The treatment includes :
• Surgery
o Goals of surgery are to remove the tumor and prevent paralysis of the face. Preserving hearing is more difficult. If a tumor is removed when it is very small, hearing may be preserved. You cannot get back any hearing that is lost before surgery. Large tumors usually result in total loss of hearing on the affected side.
o Large tumors may also press down on nerves important for movement and feeling in the face. These tumors can typically be safely removed, but the surgery often leads to paralysis of some muscles of the face.
o Extremely large tumors may also press on the brainstem, threatening other nerves and preventing the normal flow of cerebrospinal fluid. This can lead to a build-up of fluid (hydrocephalus), which can increase pressure in the head and can be life-threatening. Goals of surgery in these cases are to treat the hydrocephalus and relieve pressure on the brainstem.
• Stereotactic radiosurgery, a form of radiation therapy
o The goal is to slow or stop the tumor growth, not to cure or remove the tumor.
o Radiosurgery is often performed in elderly or sick patients who are unable to tolerate brain surgery.
o Sometimes during brain surgery to treat acoustic neuromas, not all of the tumor can be safely removed, and some of the tumor must be left behind. Radiosurgery is often used after surgery in these cases to treat the tumor that remains.
o Radiosurgery is only appropriate for small tumors, so that radiation damage to surrounding tissues can be minimized.
o Like brain surgery, radiosurgery can sometimes result in paralysis of the face or loss of hearing.
• Observation
o Since these tumors usually grow very slowly, small tumors that have few or no symptoms can be safely watched with regular MRI scans and left untreated unless they grow dangerously.
o Very often elderly patients will die of other natural causes before small, slow growing tumors show symptoms.
Outlook (Prognosis)
An acoustic neuroma is not cancer. The tumor does not spread (metastasize) to other parts of the body, but it may continue to grow and press on important structures in the skull.
Possible Complications
• Brain surgery can completely remove the tumor in most cases.
• Most people with small tumors will have no permanent paralysis of the face after surgery. However, about two-thirds of patients with large tumors will have some permanent facial weakness after surgery.
• Approximately one-half of patients with small tumors will get back useful hearing in the affected ear after surgery.
• There may be delayed radiation effects after radiosurgery, including nerve damage, loss of hearing, and paralysis of the face.
*Note*Information above is by self-reading from internet. For further information, ask your doctor. 