Definition of Non-small cell lung cancer

Non-small cell lung cancer: Cancer of the lung which is not of the small cell carcinoma (oat cell carcinoma) type. The term "non-small cell lung cancer" applies to the various types of bronchogenic carcinomas (those arising from the lining of the bronchi) which include adenocarcinoma, squamous cell carcinoma, and large cell undifferentiated carcinoma.

The distinctions between small and non-small cell lung cancer is made by looking at the tumor under the microscope and is important for proper treatment. Surgery is the treatment of choice for the early stage of non-small cell lung cancer.