Clinical and imaging features of sinonasal oncocytic papilloma

Objective:To analysze the clinical and imaging features of sinonasal oncocytic papilloma（SNOP）. Methods:The clinical data of 31 cases of SNOP confirmed by pathology from May 2006 to September 2020 were retrospectively analyzed. The common sites of the tumor, clinical symptoms, imaging features and follow-up results were analyzed. Results:Among the 31 patients, the common clinical symptoms were nasalobstructionand running nose. All the lesions were unilateral. The origin of the tumors was maxillary sinus in 17 cases, ethmoid sinus in 7 cases, frontal sinus in 4 cases, and sphenoid sinus in 3 cases. CT findings: 12 cases（38.7%） had hyperosteogeny or destruction, of which 3 cases（9.7%） showed focal osteitis. MRI findings: 25 cases（92.6%） showed cerebriform sign on T2WI or enhanced T1WI; 19 patients（70.4%） showed high or isointense signal on T1WI; 17 cases（63.0%） were associated with multiple cystoid changes. All patients were pathologically confirmed as SNOP, including 1 case with focal moderate to severe dysplasia and 1 case with carcinogenesis in situ. With follow-up 5 to 177 months, 1 case recurred, and the recurrence rate was 3.2%. Conclusion:The clinical symptoms of SNOP lack specificity and could be accompanied by polyps. The maxillary sinuses are most often involved, but other sinuses may also be affected. Nasal endoscopy and imaging examination have certain characteristics. The root pedicle of the tumor was mostly broad-based, with certain recurrence rate and malignant degeneration. Therefore, a reasonable surgical method should be selected to completely resect the lesion and reduce the recurrence.