AB018. It’s not always olfactory neuroblastoma—sinonasal undifferentiated carcinoma with frontal base and orbital involvement, a rare disease with poor prognosis: a case report

Malignant neoplasms of the paranasal sinuses and nasal cavity are rare, comprising only 3% of all head and neck malignancies. Sinonasal undifferentiated carcinoma is a rare malignancy and an aggressive neoplasm that was clinic-pathologically distinct from other poorly differentiated malignancies of the nasal cavity and sinuses. The lesion is thought to originate from the epithelium, grows rapidly and invades nearby structures, often resulting in bony destruction while rapid progression of symptoms over weeks to months is characteristic.