Giant Oncocytic Sinonasal Papilloma: A Rare Case.

Sinonasal papilloma is a rare benign neoplasm arising from the Schneiderian epithelium lining the nasal cavity and paranasal sinuses. It is classified into three histological subtypes: exophytic, inverted, and oncocytic, the latter being the least common. We report a case of a giant oncocytic sinonasal papilloma treated by endoscopic surgery, highlighting the diagnostic approach and comparing the findings with the existing literature. Histopathological examination confirmed the diagnosis. Immunohistochemical analysis demonstrated p53 positivity in both the cytoplasm and nucleus, and Ki-67 showed a low labeling index. The patient underwent complete excision via an endoscopic approach. Notably, the lesion was larger than those typically described in the literature. An 18-month follow-up revealed no complications or evidence of recurrence. It is important to bear in mind that a combined tomographic and histopathological evaluation is essential for accurate diagnosis and therapeutic approach.