Selected epithelial sinonasal neoplasms: an update

Abstract

Abstract Sinonasal neoplasms comprise 3% of all head and neck cancers and 1% of all malignancies. Malignant lesions are more common than benign ones and generally carry poor prognosis. Patients in most cases are asymptomatic and only present in advanced clinical stage with non-specific obstructive symptoms. Conventional squamous cell carcinomas are the most common carcinomas in the sinonasal tract; however, other there is an array of uncommon high grade malignancies, including poorly differentiated carcinomas, which present a diagnostic challenge due to overlapping microscopic findings in small biopsies. Distinguishing high-grade epithelial malignancies such as sinonasal undifferentiated carcinoma (SNUC), non-keratinizing squamous cell carcinoma, nuclear protein in testis (NUT) carcinoma, SMARCB1-deficiency carcinoma and HPV-related multiphenotypic sinonasal carcinoma can be difficult and almost invariably will require the use of ancillary studies to establish a definitive diagnosis.