Sinonasal Oncocytic Papilloma

**Semantic type:** Neoplastic Process

**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.

**Synonyms:** - Oncocytic Schneiderian Papilloma - Oncocytic Schneiderian papilloma - Sinonasal Oncocytic Schneiderian Papilloma - Sinonasal Papilloma, Oncocytic Type