Management of Recurrent Vestibular Schwannomas

Abstract

Objective: Management of recurrent vestibular schwannomas(VS) after microsurgery or radiosurgery is a complicated subject. However, few studies have documented the outcome of recurrent VS. The authors review clinical experience of recurrent VS management and analyzed the efficacy of treatment modalities. Methods: Between 1990 and 2002, 293 patients harboring unilateral VS underwent, microsurgery, radiosurgery, microsurgery followed by radiosurgery. Of these, 26 procedures (in 20 patients) were performed to treat recurrent VS. Recurrence was assessed from an increased tumor size by magnetic resonance imaging(MRI). The mean age of patients with recurred VS was 46.9 years and the mean follow-up period was 68 months. Radiological characteristics were investigated and growth rates of recurred tumors were calculated by measuring changes in tumor diameter on MRI after treatment. Results: MRI characteristics revealed a lobulated contour in 75% and a cyst in 60% of the patients. Only 1 patient showed neither lobulation nor a cyst. The average diameter of the recurrent tumors were 36.9 mm. The overall tumor control rate for initial management was 87.4%, 94.7%, and 98.5% for microsurgery, radiosurgery, and microsurgery plus radiosurgery, respectively. However, control rates for recurrent tumors were lower at 85%, 63%, and 80%, respectively. Conclusion: A cystic nature and a lobulated tumor contour are frequent clinical characteristics of recurrent VS. Microsurgery or microsurgery followed by radiosurgery shows little difference in tumor control rate for primary and recurrent VS. However, radiosurgery alone appears to be less beneficial for recurrent VS.