stage 0 nasal cavity and ethmoid sinus carcinoma in situ (... NAY-zul KA-vih-tee … ETH-moyd SY-nus KAR-sih-NOH-muh in SY-too)
Abnormal cells are found in the innermost lining of the nasal cavity or ethmoid sinus. These abnormal cells may become cancer and spread into nearby normal tissue.