Function Sparing Enucleation of Extracranial Schwannomas: Outcomes of 100 Patients over 20 Years

Introduction: Complete surgical resection is the standard treatment for extracranial schwannomas of the head and neck but often requires complete nerve sacrifice. This study evaluates functional outcomes and recurrence rates following intracapsular enucleation of extracranial schwannomas over a 20-year period.

Methods: A retrospective cohort study assessed patients who underwent enucleation of extracranial schwannomas between June 2003 and August 2023 at a tertiary academic center. Recurrence was assessed via serial imaging and clinical exams, while true vocal cord (TVF) function was evaluated using nasolaryngoscopy. Cranial nerve (CN) dysfunction and Horner’s syndrome were assessed through physical exams at 1 week, 6 months, and 12 months postoperatively. Multivariate logistic regression analyzed associations between schwannoma origin, tumor size, and age with postoperative CN dysfunction.

Results: A total of 101 patients underwent intracapsular enucleation of extracranial schwannomas. Patients were predominantly White (88%) and female (67%), with a mean age of 50 years (range 16–75). Schwannomas originated from the vagus nerve (46.5%), sympathetic chain (38.6%), cervical/brachial plexus (8.9%), and other cranial nerves (5.9%). The mean tumor size was 4 cm (range 1.4–8.6 cm). Among 66 patients with postoperative imaging, no recurrences were observed over a mean follow-up of 30 months (range 1–193 months). In the vagal schwannoma cohort, 53.5% had normal TVF function on POD1, improving to 79% by POD365. After sympathetic schwannoma enucleation, 90% experienced Horner’s syndrome, with 86% showing improvement or resolution in an average of 9.5 months. Multivariate analysis showed no significant association between age (p=0.8) or tumor size (p=0.9) and CN dysfunction on POD1 but found vagal schwannomas significantly associated with CN dysfunction (OR 39.0, 95% CI [7.36–723], p< 0.001).

Conclusions: Intracapsular enucleation of schwannomas is an effective approach to treatment that allows for preservation of the cranial nerves with strong functional outcomes and very low rates of recurrence.