Hypoglossal schwannomas: A systematic review of the literature. (April 2019)

• Record Type: Journal Article
• Authors: Bindal, Shivani; El Ahmadieh, Tarek Y.; Plitt, Aaron; Aoun, Salah G.; Neeley, Om James; El Tecle, Najib E.; Barnett, Samuel; Gluf, Wayne
• Is Part Of: Journal of clinical neuroscience. Volume 62(2019)
• Page Start: 162
• Page End: 173
• Publication Date: 2019-04
• Subjects: Hypoglossal schwannoma -- Cranial nerve 12 -- Twelfth nerve -- Skull base mass -- Peripheral schwannoma -- Neck swelling; Brain -- Surgery -- Periodicals; Neurosciences -- Periodicals; Nervous system -- Surgery -- Periodicals; Brain -- surgery -- Periodicals; Neurosurgical Procedures -- Periodicals; Neurosciences -- Periodicals; Electronic journals; 616.8
• DOI: 10.1016/j.jocn.2018.11.037
• Languages: English
• ISSNs: 0967-5868

Abstract

Highlights: Schwannomas of the hypoglossal nerve account for a very small percentage of non-vestibular schwannomas. Current evidence suggests overall favorable outcomes with surgical resection of hypoglossal schwannomas. A large percentage of patients (67%) experience mild and usually well-tolerated neurologic deficit. Abstract: Background: Schwannomas of the hypoglossal nerve are rare and account for a very small percentage of non-vestibular schwannomas. Objectives: In this systematic review of the literature, we examined the epidemiology, symptomatology, management, and outcomes of patients with hypoglossal schwannomas. Methods: The electronic database Pubmed was searched for all reports of hypoglossal schwannomas with descriptions of symptoms, management, and outcome characteristics. Data was extracted from each study and compiled in a spreadsheet. Continuous variables were reported as means and medians. Categorical variables were reported as proportions. Additional analysis was not done due to inconsistent reporting of outcomes and small sample sizes. Results: A total of 59 studies (94 total individual cases) were included. 64% of patients were female with mean age of 44.6 years. The majority were intracranial/extracranial (50%). The most common symptoms were tongue deviation or speech disturbance (38%) and headaches (33%). Hypoglossal nerve dysfunction was present in 80% of patients. Surgical excision was performed in 93%, with a 15% complication rate. Evidence of residual mass after surgery was noted in 29%. Permanent hypoglossal nerve deficits occurred in 67%. Recurrence of tumor burden was reported in 6 studies, with median time to recurrence of 16.5 months. Conclusion: Current evidence suggests overall favorable outcomes with surgical resection of hypoglossal schwannomas, with a large percentage of patients experiencing mild and usually well-tolerated neurologic deficit. Limitations of this study include the use of retrospective data taken from case reports/series with highly selected patients, selective reporting, and absence of control groups.