Olfactory neuroblastoma with orbital protrusion arising in the background of maxillary carcinoma.

An uncommon entity in the class of malignant neuroectodermal nasal tumors is the olfactory neuroblastoma, which originates in the roof of the nasal cavity from the olfactory epithelium. It is often mistaken by clinicians for a nasal polyp because it presents with indistinct features such as nasal obstruction and secondary sinus disease. Olfactory neuroblastoma has been observed to cause morbidity by distant metastasis, invasion through the cribriform plate, and secondary meningitis in most instances. It exhibits a range of biologic activities, from slow growth accompanied by long-term patient survival to a very aggressive malignancy with extensive metastases. We report the incidence of a rare case in which a patient, previously operated on and irradiated for squamous cell carcinoma of the maxilla, developed an olfactory neuroblastoma with orbital protrusion.