Treatment of sinonasal undifferentiated carcinoma with neoadjuvant chemotherapy and proton therapy

Abstract Sino nasal undifferentiated (SNUC) is a highly aggressive neoplasm of the nasal cavity and paranasal sinuses. SNUC is characterized by poor differentiation making the diagnosis difficult to distinguish from other tumors of the sinonasal tract. The imaging features of SNUC are nonspecific and patients often present with an advanced stage neoplasm following rapid onset of symptoms. Given the rarity and aggressive nature of SNUC, the optimal treatment remains to be determined. The prognosis is poor and the literature is limited to case reports and case series. Survival rate is estimated to be 5 years with a wide variation throughout the literature. We present a unique case of a 31-year-old Bosnian male who presented with headaches, facial pain, and epistaxis. MRI of the head revealed a destructive sinonasal mass with intracranial extension into the anterior cranial fossa, right cavernous sinus and the sella/pituitary gland. Biopsy of the paranasal sinus revealed a discohesive epithelioid neoplasm with necrosis, consistent with high grade nasopharyngeal carcinoma. We reviewed this case in the setting of reported literature concerning SNUC with emphasis on the epidemiology, pathology, diagnosis, and emerging management protocols of SNUC.