Purpose: NF2-related schwannomatosis (NF2) patients are predisposed to develop multiple peripheral and central nervous tumors including bilateral vestibular schwannomas (VS). Decision on patient management, especially in large growing tumors, might be challenging concerning possible treatment-related complications and quality of life. Systemic therapy with bevacizumab has been reported to slow VS growth and improve hearing. Here, we present single-center outcomes of NF2 patients treated with bevacizumab.
Methods: We conducted a retrospective analysis of 15 NF2 patients with morphologically diagnosed unilateral or bilateral VS indicated for systemic therapy with bevacizumab (5 mg/kg every 2 weeks) in 2015-2022. Tumor growth rate, volume, and hearing thresholds were assessed before, during, and after first-line bevacizumab therapy.
Results: 15 patients (5 male, 10 females, mean age at the start of the therapy 30y, mean no. of bevacizumab cycles 35) and 25 tumors were evaluated. Radiologically significant (> 20% from the baseline) tumor volume reduction was observed in 5 patients. Notably, in patients with bilateral VS, volume reduction occurred on only one side. Three patients demonstrated a significantly reduced growth rate and tumor stabilization. Hearing improvement was documented in 1 patient, while another experienced significant hearing decline.
Conclusion: Bevacizumab therapy may contribute to tumor shrinkage and hearing stabilization in NF2 patients. However, treatment response is variable, with meaningful tumor reduction and hearing improvement observed only in a minority of cases.
Keywords: Bevacizumab; Neurofibromatosis; Schwannomatosis; Vestibular schwannoma.
© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.