Glossopharyngeal schwannoma a rare case report: Diagnostic and surgical approach

Abstract

Introduction and importance: Schwannomas are tumors of the nerve sheath that consist of Schwann cells that are often described as slow-growing. Glossopharyngeal schwannomas are rare tumors present in the region of the posterior fossa, with limited case reports present in literature. While patients may present asymptomatically, some present with vestibulocochlear symptoms or lower cranial nerve dysfunction.

Clinical presentation: We report an extremely rare case of a left para-pharyngeal carotid space glossopharyngeal schwannoma in a 26-year-old female. The presentation was a 3-month left sided neck swelling and a hoarse voice. Radiological investigations were completed (neck ultrasound; CT; MRI scans). Investigations revealed a solid lesion measuring about 29 × 10 mm. The final decision was to excise the mass under microsurgery.

Clinical discussion: CN 9-11 schwannomas are often called jugular foramen schwannomas. Intraoperatively, these get differentiated as glossopharyngeal schwannomas. Diagnosis involves a physical examination, a detailed history, audiological assessments, and radiological investigations. While MRI scans are known as the most effective pre-operative diagnostic test, cases are in majority discovered intra-operatively. Surgical excision is the recommended approach. Post-operative recurrence is rare. Pre-operative diagnosis is often difficult due to the rarity and similarly presenting differential diagnoses.

Conclusion: Schwannomas of the glossopharyngeal nerve are extremely rare tumors that may present with lower cranial nerve or vestibulocochlear deficits. Magnetic resonance imaging is a useful tool in diagnosing this unordinary tumor. This case report intends to provide further data regarding the clinical presentation, the patient population, and the diagnostic and surgical approach in dealing with this incredibly rare tumor.

Keywords: Glossopharyngeal nerve; Neck mass; Rare; Schwannoma.