Neurofibromatosis Type 2

Treatment

The treatment of neurofibromatosis type 2 (NF2) is complex and requires a sophisticated, experienced, and well-coordinated team.

At Mayo Clinic, the team may include these specialists:

• A neurologist (specializes in diseases of the nervous system)
• An otologist (specializes in the treatment of ear diseases)
• A neurosurgeon (a brain surgeon)
• A radiologist (specializes in interpreting medical images)
• A radiation oncologist (specializes in radiation therapy)
• A geneticist (specializes in inherited disorders)

Three treatment options are available for NF2:

• Observation
• Remove or partially remove the tumor
• Stereotactic radiation therapy (radiosurgery)

Observation

If the tumor is discovered when it is very small and has subtle symptoms, careful observation over time may be appropriate for some patients, since many of the tumors associated with neurofibromatosis type 2 grow slowly.

Magnetic resonance imaging of the head is done periodically to monitor tumor growth. If there is no growth, observation is continued. But if the tumor size increases, treatment may become necessary.

A small tumor diagnosed in an older patient may only require close watching, if disabling symptoms are not present. Some tumors don't appear to grow, so treatment and its potential risks and complications can sometimes be avoided.

Another group of people for whom observation may be preferred are those who have a tumor in their only hearing ear or better-hearing ear. In such cases, growth is monitored and surgery is considered only if hearing is lost or the tumor size becomes life threatening. Hearing aids may be helpful early in the course of the disease.

If hearing cannot be preserved or restored, then hearing rehabilitation options are considered — such as hearing aids, cochlear implants, brainstem implants and hybrid devices (a cochlear implant and conventional hearing aid combination). Mayo's cochlear implant team is well established and is investigating the two most advanced devices available. (See treatment of hearing disorders.)

Early recognition of effects on vision due to NF2 is extremely important. Routine eye examinations should be part of the care of all those who have NF2.

Surgical Tumor Removal

The goal of surgery is to remove the tumor and avoid any new neurologic deficit such as facial weakness or hearing loss. Success in achieving these goals depends on the size and configuration of the tumor.

Surgery is done under general anesthesia using an microscope to enlarge the field of vision. Usually, patients stay in the hospital four to five days after surgery.

Various surgical approaches are used to remove tumors associated with NF2. The choice depends on the location, tumor size, and the skill and experience of the surgeon. Each approach has advantages and disadvantages, and excellent results have been achieved in all of the approaches. The surgeon and patient should thoroughly discuss the reasons for a selected approach.

Partial Tumor Removal

Some patients and their surgeons prefer to remove part of a tumor, especially if the tumor is large, realizing that more surgery or radiosurgery may be needed later. Reducing the tumor size may

• Eliminate the threat to the patient's health during his or her life span
• Reduce the probability of facial nerve dysfunction as a result of the surgery

This surgery still carries a risk for hearing loss. Periodic MRI scans are important to follow the potential growth of the remaining tumor.

Stereotactic Radiosurgery

Stereotactic radiosurgery delivers a precise dose of radiation to the tumor, with a goal of stopping tumor growth. It is usually performed on an outpatient basis, using local anesthesia. Radiosurgery is often used to treat remaining tumor tissue following surgery in which not all of the tumor can be safely removed.