A Case of Nasal Chondromesenchymal Hamartoma Misunderstood as a Sphenochoanal Polyp in an Adult

Nasal chondromesenchymal hamartoma (NCMH) is a rare example of hamartoma and mainly involves the nose and paranasal sinuses. We report a case of NCMH in a 24-year-old Asian adult, which was misunderstood as a sphenochoanal polyp. Endoscopic examination showed the nasal passages were obstructed with a polypoid mass originated from left posterior ethmoid and sphenoidal sinus. Computed tomography (CT) demonstrated non-enhancing bulging soft masses. The patient underwent left endoscopic sinus surgery and resection of left sphenochoanal polypoid mass. Histopathology showed an inflammatory polyp with chondroid metaplasia. After 18 months, the patient visited the hospital again with a recurred polypoid mass at the same area. Revision endoscopic sinus surgery was performed. Finally, based on the histologic findings and results of immunohistochemistry, the nasal polyp was diagnosed as chondromesenchymal hamartoma. In the case of chondroid proliferations of the nose and paranasal sinuses, NCMH should be considered a differential diagnosis. (J Clinical Otolaryngol 2017;28:238-242)