A 57-year-old man presented with a history of nasal obstruction of five to six years duration. 'Nasal polyps' were removed on several occasions. He had previously had an episode of paraplegia which resolved after the removal of a spinal tumour. Histology from both sites was thought to represent a malignant fibrous histiocytoma. On presentation the patient had computed tomographical (CT) evidence of extensive ethmoidal disease, with threatened intracranial extension. He also had evidence of lung and retroperitoneal disease with pancreas and kidney involvement. The ethmoidal disease was considered potentially lethal and therefore a craniofacial resection was performed. Review of all the histology revealed that the diagnosis was extranodal Rosai–Dorfman disease (sinus histiocytosis). The patient's course is described, and the literature on this disease of unknown aetiology is reviewed.
