SMARCB1-Deficient Sinonasal Carcinoma

**Semantic type:** Neoplastic Process

**Definition:** An SWI/SNF-deficient sinonasal carcinoma characterized by biallelic deletion or inactivating mutation of SMARCB1 gene. It usually affects the paranasal sinuses, especially ethmoid. It is composed of a monomorphic malignant epithelial cellular population with a predominantly basaloid or plasmacytoid/rhabdoid morphology.

**Synonyms:** - Sinonasal SMARCB1-Deficient Carcinoma