BACKGROUND: Facial nerve schwannomas are rare, challenging tumors to manage due to their nerve of origin. Functional outcomes after stereotactic radiosurgery (SRS) are incompletely defined. OBJECTIVE: To analyze the effect of facial nerve segment involvement on functional outcome for these tumors. METHODS: Patients who underwent single-session SRS for facial nerve schwannomas with at least 3 mo follow-up at 11 participating centers were included. Preoperative and treatment variables were recorded. Outcome measures included radiological tumor response and neurological function. RESULTS: A total of 63 patients (34 females) were included in the present study. In total, 75% had preoperative facial weakness. Mean tumor volume and margin dose were 2.0 ± 2.4 cm3 and 12.2 ± 0.54 Gy, respectively. Mean radiological follow-up was 45.5 ± 38.9 mo. Progression-free survival at 2, 5, and 10 yr was 98.1%, 87.2%, and 87.2%, respectively. The cumulative proportion of patients with regressing tumors at 2, 5, and 10 yr was 43.1%, 63.6%, and 63.6%, respectively. The number of involved facial nerve segments significantly predicted tumor progression (P = .04). Facial nerve function was stable or improved in 57 patients (90%). Patients with involvement of the labyrinthine segment of the facial nerve were significantly more likely to have an improvement in facial nerve function after SRS (P = .03). Hearing worsened in at least 6% of patients. Otherwise, adverse radiation effects included facial twitching (3 patients), facial numbness (2 patients), and dizziness (2 patients). CONCLUSION: SRS for facial nerve schwannomas is effective and spares facial nerve function in most patients. Some patients may have functional improvement after treatment, particularly if the labyrinthine segment is involved.

Clinical Oncology Department Ain Shams University Cairo Egypt

Department of Neuro oncology Cleveland Clinic Cleveland Ohio

Department of Neurosurgery Neurologic Institute Taipei Veterans General Hospital Taipei Taiwan

Department of Neurosurgery New York University School of Medicine New York New York

Department of Neurosurgery Université de Sherbrooke Centre de Recherche du CHUS Sherbrooke Canada

Department of Neurosurgery University of Pittsburgh Medical Center Pittsburgh Pennsylvania

Department of Neurosurgery University of Virginia Medical Center Charlottesville Virginia

Department of Radiation Oncology Mayo Clinic Jacksonville Florida

Department of Radiation Oncology NYU Langone Medical Center New York New York

Department of Stereotactic and Radiation Neurosurgery Na Homolce Hospital Prague Czech Republic

Division of Neuro otology House Ear Institute Los Angeles California

Division of Neurosurgery House Ear Institute Los Angeles California

Gamma Knife Center Cairo Nasser Institute Hospital Cairo Egypt

Max Rady College of Medicine University of Manitoba Winnipeg Canada

Neurosurgery Department Ain Shams University Cairo Egypt

Neurosurgery Department Benha University Qalubya Egypt

Radiation Oncology Department National Cancer Institute Cairo University Cairo Egypt

School of Medicine National Yang Ming University Taipei Taiwan

Section of Neurosurgery University of Manitoba Winnipeg Canada

Neurosurgery. 2020 Dec 15;88(1):E99-E101. doi: 10.1093/neuros/nyaa350. PubMed

References provided by Crossref.org

Facial Nerve Schwannoma Treatment with Stereotactic Radiosurgery (SRS) versus Resection followed by SRS: Outcomes and a Management Protocol