Comparison of Radiologic Characteristics between Inverted Papilloma and That Associated with Squamous Cell Carcinoma

ABSTRACT

BACKGROUND AND OBJECTIVES: Inverted papilloma (IP) is not infrequently associated with squamous cell carcinoma (SCCa). Preoperative punch biopsy for the nasal mass of patients with associated carcinoma often results only in an inverted papilloma, which is followed by an inadequate surgery. In this study, the authors aim to differentiate the inverted papilloma associated with carcinoma from the simple inverted papilloma in the preoperative CT scan. MATERIALS AND METHODS: Between January, 1997 and February, 2005, twelve cases of IP with carcinoma (IP+SCCa) were diagnosed and treated at the Department of Otolaryngology, Asan Medical Center. The control group, made up of twenty-six cases of IP, was selected randomly during the same period. We analyzed the paranasal sinus CT (PNS CT) findings and reviewed medical records of the patients. The CT characteristics such as calcification, bridging the antronasal border, heterogenous enhancement, tumor necrosis, bony thickening, choanal extension, bony remodeling, bony destruction and surrounding structures were compared between the two groups. RESULTS: Both the IP and the IP+SCCa had developed unilaterally. The most common site was the middle meatus in the IP and the ethmoid sinus in the IP+SCCa. On the PNS CT, the IP+SCCa had intraorbital and pterygopalatine fossa invasion were more frequent than in the IP. Bony thickening and bone destruction were the statistically significant findings that favor the IP+SCCa (p=0.049 & p=0.000). CONCLUSION: Bone destruction of the maxillary sinus wall in the preoperative PNS CT suggests the association of SCCa among the IP patients. Preoperative instruction for the patients and surgical planning for the possible SCCa should be strongly considered.