Parapharyngeal Schwannoma: Limitations Regarding Diagnosis and Surgical Intervention-A Case Report and Focused Literature Review.

Background: Parapharyngealspace schwannomas are rare benign tumors that may become significantly enlarged prior to producing symptoms. Their deep anatomical location and proximity to major neurovascular structures may pose significant challenges for diagnosis and surgical management. Case Presentation: A 51-year-old woman presented with a slowly enlarging, painless right-side neck mass. Contrast-enhanced CT-scan demonstrated a large, well-circumscribed post-styloid parapharyngeal mass measuring approximately 44 × 53 × 73 mm, displacing rather than invading the adjacent carotid vessels. Paraganglioma was included in the differential diagnosis. MRI-scan was not performed because the CT-scan provided sufficient anatomical information for surgical planning in our clinical setting. The tumor was completely removed through an extended transcervical-cervico-parotidial approach without capsular lesions. The origin nerve was not identified intraoperatively. The histopathological exam confirmed a benign schwannoma. No clinically apparent neurological deficit was observed at the 6- and 12-months follow-ups. Literature Review: A focused literature review of PubMed, Scopus, and Web of Science was performed to contextualize the clinical findings and surgical management. The literature highlights the difficulty of determining the nerve of origin preoperatively and the overlap between post-styloid schwannomas and paragangliomas on imaging studies. Surgical excision remains the main treatment, although evidence regarding optimal surgical technique, long-term functionality and disease-control outcomes remain controversial. Conclusions: This case-study highlights the diagnostic challenges of large post-styloid parapharyngeal schwannomas and the limitations of imaging studies in establishing the nerve of origin. Surgical management should be individualized according to tumor anatomy, spatial neurovascular relationships, and anticipated functional risks.