The ethmoid sinus is a collection of approximately nine air cells situated between the upper limit of the nasal fossa and the orbit and closely related to the posterio superior aspect of the maxillary antrum. Cancer in any of these regions may spread rapidly to the adjacent areas, especially as the early disease is frequently asymptomatic. Cancer involving the ethmoid sinus alone is therefore a rare entity, but is more usually part of an uncommon regional disease. A series of 715 tumors of the upper jaw collected by Lederman et al22 over a period of 35 years included 176 cases of ethmoid cancer, ie, 25%.
The basement membrane lining the sinus easily undergoes squamous metaplasia, and approximately 50% of the tumors are squamous cell carcinoma of varying degrees of differentiation, the majority of which are poorly differentiated. The remaining lesions include adenocarcinoma, lymphoma, Ringertz tumor, sarcoma, melanoma, and the