An elderly woman presented with vertigo and loss of memory. Computed tomography, positron emission tomography–computed tomography scan, and magnetic resonance imaging studies demonstrated a right ethmoid mass with evidence of bony erosion. The patient had no nasal symptoms. Endoscopy showed a polypoid mass in the right olfactive cleft. Operative biopsy wavered between benign seromucinous hamartoma and low-grade adenocarcinoma. The patient underwent a complete excision of the mass. Final histology de!nitively proved the presence of a seromucinous hamartoma. No adverse events were noted. No adjuvant treatment was delivered. Follow-up was reassuring at 1 year.
Cite this article as: Nève de Mévergnies J-G, Eloy P. Seromucinous hamartoma versus low-grade sinonasal adenocarcinoma: A worrying mass of the ethmoid sinus. Eur J Rhinol Allergy 2025;8(1):36-40.