Sino nasal undifferentiated carcinoma – A diagnostic conundrm

Abstract

Sinonasal undifferentiated carcinoma (SNUC) is a rare and highly aggressive tumour frequently arising from the maxillary sinus and nasal cavity. Here we report a 34-year-old female patient who presented with a pale polypoidal mass which bleeds on touch involving the left nasal cavity and nasopharynx. Imaging showed a multilobulated lesion involving the left nasal cavity and left paranasal sinuses with extension into the left masticator space, pterygopalatine fossa and retropharyngeal space supplied by a branch of the left maxillary artery. It suggested a possibility of a benign vascular mass lesion. The mass was surgically removed via the maxillary swing approach. Immunohistochemical analysis showed epithelial origin (AE1/AE3+, EMA+) and no reactivity for neuroendocrine, melanocytic, hematolymphoid, or mesenchymal markers. A diagnosis of SNUC was reached and the patient was given concurrent radiotherapy and chemotherapy. The patient is disease free one year post surgery. To conclude, a vigilant correlation of clinical, microscopic, and immunohistochemical characteristics is essential for early diagnosis and optimal management of SNUC.