A 65-year-old woman presents with unilateral epistaxis and a darkly pigmented polypoid mass in the nasal cavity. Biopsy shows epithelioid cells with intracytoplasmic pigment. Which of the following is the most common primary site for sinonasal mucosal melanoma?

• A Ethmoid sinus
• B Maxillary sinus
• C Nasal septum ✓
• D Frontal sinus

Explanation

Sinonasal mucosal melanoma most commonly arises on the nasal septum, followed by the inferior and middle turbinates. It is less common in the paranasal sinuses, with the maxillary and ethmoid sinuses being less frequent primary sites than the nasal cavity proper. The frontal sinus is a rare site for any sinonasal malignancy.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.