Isolated inverting papilloma of the sphenoid sinus: clinical presentations, imaging manifestations, and therapeutic strategies.

Background: Isolated inverting papilloma (IP) of the sphenoid sinus is rare, with about 50 patients reported in the English-language literature. With its rarity, scientists have paid less attention to the clinical and radiographic characteristics of isolated IPs arising from the sphenoid sinus.

Methods: We describe the clinical presentation, imaging manifestations, and surgical methods of isolated IPs from the sphenoid sinus in 3 patients and review the English-language literature from 1970 to 2011.

Results: In total, 59 cases of isolated sphenoid sinus IPs (including our cases) have been reported, 40 patients with computed tomography or magnetic resonance imaging details. The most common presentation is headache. Lesions were found in the sphenoethmoidal recess in 26 cases. In 8 patients who underwent enhanced magnetic resonance imaging, the tumor was obviously intensified. We found 26 patients with bony destruction, and 8 lesions revealed the correct tumor origin.

Conclusions: A polyp-like mass in the sphenoethmoidal recess strongly implied the diagnosis of an IP in the sphenoid sinus. Bony destruction on computed tomography is a common characteristic of this disease and had a close relationship with the original tumor site in our study. Malignant transformation of IPs in the sphenoid sinus is much scarcer.