Sinonasal Small Cell Neuroendocrine Carcinoma

**Semantic type:** Neoplastic Process

**Definition:** A rare neuroendocrine carcinoma that arises from the nose and paranasal sinuses and is composed of malignant small cells. The mitotic count is more than 10 per 2 mm2 and/or the Ki-67 index is more than 20%.

**Synonyms:** - Nasal Cavity and Paranasal Sinus Small Cell Carcinoma - Nasal Cavity and Paranasal Sinus Small Cell Neuroendocrine Cancer - Nasal Cavity and Paranasal Sinus Small Cell Neuroendocrine Carcinoma - Sinonasal Small Cell Carcinoma - Sinonasal Small Cell Carcinoma