Study, new technique help personalize acoustic neuroma surgery decision


When someone learns he has a brain tumor, the natural impulse is to want it out quickly.

That can present a dilemma for surgeons when the patient has an acoustic neuroma. These are benign tumors that grow on the nerve that affects balance.

Some of these tumors may not continue to grow and impact quality of life for years. Taking them out can cause hearing loss or other complications.

On the other hand, not removing them may allow them to grow. They may become more difficult to remove and pose other risks.

A report from Vanderbilt University Medical Center now offers more guidance for surgeons and patients facing treatment choices.

The study of 564 people with acoustic neuromas found that larger tumors were more likely to grow. Smaller ones may be safely watched for years. Patients whose symptoms include imbalance also had a greater chance of seeing their tumors grow.

“Following patients gives us information on growth rates and allows us to make better decisions on care and achieve better outcomes,” said David Haynes, M.D., one of the study’s authors. Haynes is chief of the neurotology division at Vanderbilt.

“A slow-growing tumor may not require intervention immediately, or possibly at all.”

In current practice, smaller tumors are routinely removed.

The report also offers comfort to patients, said Reid Thompson, M.D., chair of neurological surgery at Vanderbilt.

“Their first reaction is to want the tumor treated immediately,” Thompson said. “Developing a plan with patients requires a careful balance of risk and benefits. This study helps to clarify decision making with patients and avoids exposing patients to unnecessary risk.”

Researchers also considered hearing in the patients with small tumors. For patients whose tumors were watched, 94 percent of them maintained hearing after a year, 65 percent after five years, and almost 50 percent after 10 years.

For many patients, surgery remains an important choice as a first option or if tumors that are being watched start to grow, Haynes said. But the findings underscore the importance of taking a personalized approach to each patient in deciding whether or when to remove the tumor.

Because acoustic neuromas are rare, only a few centers in the country see enough patients to do this type of in-depth analysis. The extensive 20-year study is the largest ever published on the subject and is the latest in a series of three papers from Vanderbilt experts. The results were published in the journal Otology & Neurotology.

When surgery is needed

Teams that treat large numbers of patients also are able to develop expertise and skill in the most advanced techniques. An example is an approach that is less invasive that traditional surgery and can be an option for patients whose small tumors need to come out.

Vanderbilt recently became the second center in the country -- and only third in the world -- to use this “endoscopic” surgery to remove an acoustic neuroma.

Traditionally, tumors of the ear are removed by drilling into the bone behind the ear and performing the surgery with a microscope. That is still the method used to remove large tumors, said Alejandro Rivas, M.D., a Vanderbilt ear, nose and throat surgeon.

For smaller tumors, however, the endoscopic method offers an alternative.

An endoscope is a flexible rod with a lens at the end and fiber optics inside. It projects a large, magnified image onto a screen. It lets surgeons see around bends in the ear canal. Used along with surgical instruments, it allows surgeons operate through the ear canal with little or no incision.

“From a patient’s perspective, there are a lot of advantages,” Rivas said.

“It decreases pain. It has very similar, and in some cases better, outcomes than using a traditional technique, with less post-operative care. It’s ideal for children because there are no incisions and children bounce back much faster.”

Adapted from the VUMC Reporter.