NCIt definition : A benign neoplasm with exophytic and endophytic growth arising from the lateral nasal
wall or the paranasal sinuses. It is characterized by the proliferation of columnar
cells with oncocytic features. Microcysts containing mucin and neutrophils are present
in the epithelium. Clinical manifestations include nasal obstruction and epistaxis.
Occasionally, it is associated with the development or presence of a carcinoma, usually
squamous cell carcinoma.;