CyberKnife Stereotactic Radiosurgery for Vestibular Schwannomas: Systematic Review and Meta-Analysis of Long-Term Tumor Control and Hearing Preservation Outcomes

Nolan J Brown; Zach Pennington; Saarang Patel; Clifford Jiajun He; Brian V Lien; Redi Rahmani; Julian Gendreau; Joshua S Catapano; Shawn M Stevens; Michael T Lawton

doi:10.1227/neuprac.0000000000000202

CyberKnife Stereotactic Radiosurgery for Vestibular Schwannomas: Systematic Review and Meta-Analysis of Long-Term Tumor Control and Hearing Preservation Outcomes

Neurosurg Pract. 2026 Feb 2;7(1):e000202. doi: 10.1227/neuprac.0000000000000202. eCollection 2026 Mar.

Authors

Affiliations

¹ Department of Neurosurgery, University of California, San Diego, San Diego, California, USA.
² Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA.
³ Department of Neurosurgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
⁴ Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
⁵ Otolaryngology and Lateral Skull Base Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.

Abstract

Background and objectives: Stereotactic radiosurgery is a popular intervention for small vestibular schwannomas in patients with preserved hearing. Gamma Knife radiosurgery (GKRS) and CyberKnife radiosurgery (CKRS) represent 2 alternative modalities, with CKRS potentially allowing for the delivery of higher doses over multiple sessions. However, the optimal dosing and hearing outcomes of CKRS remain unclear. This study systematically reviewed all literature describing outcomes following treatment of vestibular schwannomas with CKRS, with a focus on tumor control, hearing preservation, and dosing schema.

Methods: The PubMed, Scopus, and Embase databases were queried to identify primary retrospective studies reporting local tumor control and hearing preservation rates following CKRS for vestibular schwannoma. Studies were reviewed, and the systematic review and meta-analysis were performed according to PRISMA and meta-analysis guidelines.

Results: Fifteen studies with study periods ranging from 1998 to 2018 were included. These studies comprised 2018 patients (mean age, 60.2 years; range, 11-91 years; 52% female), of whom 64 had neurofibromatosis type 2. The mean follow-up was 40 (range, 6-120) months, and 309 patients had undergone prior treatment (surgery and/or stereotactic radiosurgery). In aggregate, local control at the last follow-up was 96% (95% CI, 95%-98%), and 73% (95% CI, 66%-81%) of patients had preserved hearing. The most common major complications after CKRS were facial neuropathy (1.4%), trigeminal neuralgia (1.3%), and hydrocephalus (0.5%). CKRS provides a high rate of short-term and mid-term tumor control with hearing preservation comparable with GKRS, but long-term outcomes remain under investigated.

Conclusion: This systematic review and meta-analysis found that CKRS offers high rates of tumor control and hearing preservation in patients undergoing stereotactic radiosurgery for vestibular schwannomas. Current data suggest that CKRS is a reasonable, safe therapeutic option for patients with small tumors and preserved hearing. Further exploration in larger cohorts and direct comparison with GKRS is merited.

Keywords: Acoustic neuroma; CyberKnife; Hearing preservation; Neurosurgery; Stereotactic radiosurgery; Vestibular schwannoma.

Publication types

Review