Sinonasal NUT carcinoma mimicking acute ethmoiditis.

Nuclear protein in testis (NUT) carcinoma is a rare aggressive cancer typically affecting young adults in midline structures of the head and neck or thorax. A woman in her early 20s presented with non-specific neurological symptoms, including left-sided headache, nausea, vomiting and blurred vision. Blood tests showed slightly elevated infection parameters and imaging revealed an expansile ethmoid mass with orbital and intracranial extension mimicking severe acute ethmoiditis, prompting urgent surgery. Biopsy confirmed NUT carcinoma by immunohistochemistry. The patient underwent radical resection followed by chemo- and radiotherapy. 11 months post-diagnosis, there is no evidence of cancer. Diagnosis of sinonasal NUT carcinoma is complicated by non-specific clinical, radiological and histopathological features, compounded by limited awareness among surgeons, oncologists, radiologists and pathologists. Multidisciplinary management and increased awareness of NUT carcinoma are critical to reduce diagnostic delay and improve prognosis.