A 39-year-old female presented with persistent left-sided nasal obstruction and facial pain. Nasal endoscopy revealed a polypoid mass in the middle meatus. CT and MRI demonstrated a 2.5-cm sinonasal tumor in the posterior left nasal cavity with extension to the ethmoid and ipsilateral sphenoid sinuses, contacting the sphenopalatine foramen without significant invasion of the pterygopalatine fossa (Fig. 1). Endoscopic sinus surgery with computer-assisted navigation achieved complete piecemeal resection, following maxillary antrostomy, middle turbinectomy, unciformectomy, ethmoidectomy, and sphenoidotomy. Histopathology showed spindle-shaped cells in a loose collagenous stroma with myxoid areas and strong S100 positivity, consistent with sinonasal schwannoma. The patient had an uneventful recovery and remained recurrence-free after 2 years of follow-up.
Computed tomography (CT), axial (A) and coronal section (B) and magnetic resonance imaging (MRI), axial (C) and coronal section (D). Sinonasal tumor located in the posterior portion of the left nasal cavity measuring 2.5 cm in longitudinal axis, with extension to the ethmoidal cells and ipsilateral sphenoid sinus (*). The tumor was in contact with the sphenopalatine foramen (△) but without significant invasion into the pterygopalatine fossa.
Schwannomas are slow-growing benign tumors arising from Schwann cells of peripheral nerves. Sinonasal schwannomas are rare, accounting for <4% of head and neck cases, with the ethmoid sinus being the most frequent site, followed by the maxillary, frontal, and sphenoid sinuses. Symptoms are nonspecific, commonly including nasal obstruction, anosmia, and epistaxis. Diagnosis relies on histopathology and immunohistochemistry, as radiological features are not distinctive. Complete surgical excision with tumor-free margins is the treatment of choice, typically via an endoscopic-assisted approach. Prognosis is favorable, with malignant transformation rare and recurrence uncommon.
Ethical considerationsProcedures followed here were in accordance with the ethical standards of the responsible committee on human experimentation and with the Helsinki Declaration of 1975, as revised in 1983. We have not used patients' names, initials, or hospital numbers.
AuthorshipAll authors had access to the data and played a role in writing this manuscript.
FundingNo specific funding was received from any bodies in the public, commercial or not-for-profit sectors to carry out the work described in this article.
The authors have declared no conflicts of interest.
