Fractionated Stereotactic Radiotherapy for Facial Nerve Schwannoma

Purpose/Objectives: Facial nerve schwannomas (FNS) are rare. Retrospective data indicate that stereotactic radiosurgery for FNS may add significant morbidity in the form of facial paralysis. We present our institutional experience with fractionated stereotactic radiotherapy (FSRT) of FNS.

Materials/Methods: A total of eight patients with FNS who received radiation treatment at our institution from 1998 and 2011 were identified. We performed retrospective review. We report the radiographic response, symptom control, and toxicity associated with FSRT for FNS.

Results: The median clinical follow-up was 28 months (range, 10–51 months). All the patients presented with symptoms including pain, tinnitus, facial asymmetry, diplopia, and hearing loss. Median tumor volume was 1.96 cc (range, 0.25–12.38 cc). The median dose of radiation treatment is 50.4 Gy (range, 46.8–54 Gy) in 1.8 fractions. On most recent follow-up, 88% of patients had improvement of clinical symptoms and 12% of patients had stable clinical findings. Local control was achieved in all the patients with 37% patients having radiographic reduction in tumor size. There was no significant toxicity, except for one patient developed acute worsening of facial nerve palsy within 2 months of completing treatment. The patient's symptom resolved with conservative measures.

Conclusion: FSRT results in excellent control of FNS, high rates of symptom improvement, with minimum toxicities. FSRT may be considered as treatment of choice for preservation of facial nerve function. The result should be further validated with larger patient cohort.