Non-small cell lung cancer accounts for about 85 percent of lung cancers and includes:

• Adenocarcinoma: starts from adenomatous cells; these normally secrete substances such as mucus. This is the type found more often in current or former smokers, but also is the type commonly occurring in non-smokers. Adenocarcinoma is found more often in women than in men, and also in people of younger ages than other types. They are seen in the outer parts of the lungs in the x-rays or CTs of the chest.
• Squamous cell carcinoma, starts in squamous cells, the cells that line the inside of the airways. Usually occurs in smokers and is more often seen in the central part of the lungs, close to a main airway.
• Large cell carcinoma, appears in any part of the lung. Usually grows and spreads quickly. A subtype of large cell carcinoma, is the large cell neuroendocrine carcinoma, which is a fast-growing cancer, often very similar to small cell lung cancer.