Sinus, Oncocytic Schneiderian papilloma

Schneiderian papillomas are a group of benign neoplasms of the respiratory (Schneiderian) mucosa. They comprise 1-5% of all sinonasal tract tumours. Clinical presentation depends on the site and includes pain, discharge, airway obstruction, and epitaxis. There are three morphological subtypes: inverted, exophytic, and oncocytic.

This is a rare case of oncocytic-type Schneiderian papilloma, which tends to occur in older patients (> 60 years) and clinically presents as an exophytic or endophytic lesion growing in the lateral wall of the nasal cavity and sinuses. Microscopic findings include multiple layers of epithelial proliferation composed of columnar oncocytic epithelium with abundant eosinophilic-granular cytoplasm. The tumour stains positively for mitochondrial histochemical stains (PTAH) and cytochrome-c oxidase. Treatment is complete surgical excision with 25-35% recurrence due to incomplete surgical excision.