Twenty years’ experience in the treatment of acoustic neuromas with fractionated radiotherapy: A review of 45 cases

Maire. IJROBP 2006:66:170

To evaluate very long-term results of fractionated radiotherapy (FRT) of acoustic neuromas (AN).From January 1986 to January 2004, FRT was performed in 45 consecutive patients (46 AN). A 3-field to 5-field technique with static beams was used. A mean total dose of 51 Gy was given (1.80 Gy/fraction). The median tumor diameter was 31 mm (range, 11–55 mm). The median follow-up from FRT was 80 months (range, 4–227 months).

Nineteen patients died, two with progressive disease, and 17 from non-AN causes. A serviceable level of hearing was preserved in 7/9 hearing patients. No patient had facial or trigeminal neuropathy. Tumor shrinkage was observed in 27 (59%) and stable disease in 16 (35%). Tumor progression occurred in three patients, 12 to 15 months after FRT. Two additional tumors recurred after shrinkage 20 and 216 months after treatment and were operated on. Actuarial local tumor control rates at 5 and 15 years were 86%. For the patient who had a tumor recurrence at 216 months, histologic examination documented transformation to a low-grade malignant peripheral nerve sheath tumor.