Stereotactic Radiation an Option for Acoustic Neuromas But Hearing Loss a Risk

Age also influences whether a patient is a candidate for stereotactic radiation, said Dr. Coelho. This procedure offers an excellent alternative for elderly patients unable to tolerate surgery, he explained. However, younger patients may not want to pursue the stereotactic procedure because of the long-term potential of recurrence or developing radiation-induced malignancy.

We generally refer our young patients healthy patients to surgery because we don’t know the long-term effects of radiation, noted Dr. House. However, the procedure is indicated in older patients who have a documented growing tumor, he said.

Pre- and Post-Treatment

If stereotactic radiation is chosen, the physician needs to map the tumor with an MRI to determine treatment boundaries and the radiation dose, said Dr. House.

Patients should also receive an MRI six months after treatment to ensure that the tumor is not growing, said Dr. Bigelow. The tumor may initially show some swelling on this scan, so another MRI should be scheduled for six months later. Dr. Bigelow then sees patients once a year for an MRI and audiograms to monitor hearing.

Some tumors will start to grow again after five to 10 years, so ongoing follow-up is important, said Dr. House.

What Patients Should Know

Physicians need to provide complete disclosure of treatment options and their risks and benefits, said Dr. Coelho. Open and frequent dialogue between doctor and patient cannot be stressed enough, he said.

For example, patients should know that radiation does not cure acoustic neuromas but may prevent growth in about 80% of the tumors, said Dr. House. In contrast, at his facility, microsurgery has close to a 100% cure rate.

Some published data show higher control rates for stereotactic radiation. For example, in tumors no larger than 3 cm, control rates were 98% in a University of Pittsburgh study (N Eng J Med 1998;339:1426-33), noted Dr. Young.

When contemplating surgery, patients should remember that surgery carries the risk of infection, hemorrhage, and stroke if a blood vessel is injured, added Dr. Young. Moreover, with surgery, patients will spend three to five days in the hospital and three or four weeks recovering at home.

Surgery also has a high risk of hearing loss, depending on the size of the tumor, with smaller tumors posing less risk, said Dr. Bigelow. Patients and physicians should remember that significant risk of hearing loss exists with any treatment for acoustic neuroma.

If patients lose their hearing with surgery, this usually occurs on the day of the procedure, added Dr. Young.