A case of malignant schwannoma arising in a paranasal sinus is reported. In this case, histological hallmarks were lost because of the poorly differentiated nature of the tumour. Immunohistological techniques were applied to the diagnosis, confirming the neural origin of this tumour. Malignant schwannoma is a relatively rare disease in the nasal cavity and paranasal sinuses. For the treatment of this tumour, wide resection is recommended. In this patient, radical resection of the maxilla with orbital and ethmoid exenteration was performed. The patient recovered uneventfully with no evidence of disease three years after surgery.
