Facial Nerve Schwannomas: Review of 80 Cases Over 25 Years at Mayo Clinic

Mayo Clin Proc. 2016 Nov;91(11):1563-1576. doi: 10.1016/j.mayocp.2016.07.007. Epub 2016 Oct 5.

Abstract

Objective: To elucidate the long-term clinical behavior, treatment, and outcomes of sporadic facial nerve schwannoma (FNS) in a large cohort of patients managed in the post-magnetic resonance imaging era.

Patients and methods: Retrospective review at a single tertiary health care system (January 1, 1990, through December 31, 2015), evaluating 80 consecutive patients with sporadic FNS.

Results: Ninety-eight patients with FNS were identified; 10 with incomplete data and 8 with neurofibromatosis type 2 were excluded. The remaining 80 patients (median age, 47 years; 58% women) were analyzed. Forty-three (54%) patients presented with asymmetrical hearing loss, 33 (41%) reported facial paresis, and 21 (26%) reported facial spasm. Seventeen (21%) exhibited radiologic features mimicking vestibular schwannoma, 14 (18%) presented as a parotid mass, and 5 (6%) were discovered incidentally. Factors predictive of facial nerve paresis or spasm before treatment were female sex and tumor involvement of the labyrinthine/geniculate and tympanic facial nerve segments. The median growth rate among growing FNS was 2.0 mm/y. Details regarding clinical outcome according to treatment modality are described.

Conclusion: In patients with FNS, female sex and involvement of the labyrinthine/geniculate and tympanic segments of the facial nerve predict a higher probability of facial paresis or spasm. When isolated to the posterior fossa or parotid gland, establishing a preoperative diagnosis of FNS is challenging. Treatment should be tailored according to tumor location and size, existing facial nerve function, patient priorities, and age. A management algorithm is presented, prioritizing long-term facial nerve function.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Cranial Nerve Neoplasms / diagnosis*
  • Cranial Nerve Neoplasms / therapy
  • Diagnosis, Differential
  • Dizziness / etiology
  • Facial Nerve Diseases / diagnosis*
  • Facial Nerve Diseases / therapy
  • Facial Paralysis / etiology
  • Female
  • Headache / etiology
  • Hearing Loss / etiology
  • Hemifacial Spasm / etiology
  • Humans
  • Incidental Findings
  • Male
  • Middle Aged
  • Minnesota
  • Neurilemmoma / diagnosis*
  • Neurilemmoma / therapy
  • Patient Outcome Assessment
  • Retrospective Studies
  • Tinnitus / etiology
  • Young Adult