Sinonasal SMARCB1-deficient carcinomas were first identified independently by Bishop et al. and Agaimy et al. in 2014, characterized by deletions of the SMARCB1 gene with variable staining for neuroendocrine markers and a mainly basaloid morphology, resembling SNUC or non-keratinizing SCC [40, 41]. The gene discussed is SMARCB1; the disease is carcinoma.