Non-small cell lung cancer (NSCLC) accounts for about 87 percent of lung cancers, and small cell lung cancer (SCLC) accounts for the rest. These two varieties are based on how the cells look under a microscope. Types of NSCLC include:

• Adenocarcinoma. Cancer cells in the mucus-producing glandular cells of the lungs in the bronchi and bronchioles. This is the most common type of lung cancer, accounting for about 40 percent of all lung cancers. This cancer rarely shows symptoms in the early stages and therefore may have metastasized by the time of diagnosis.  It is more likely than the other kinds of NSCLC to begin in the peripheral cells of the lungs and to spread outside of the lungs.
  
  
• Bronchioalveolar carcinoma. This subtype of adenocarcinoma often has spread within the lung before it is discovered.
  
  
• Squamous (epidermoid) cell carcinoma. Cancer of the cells lining the bronchi or airways in the central part of the lungs. These cells are thin and flat and look like fish scales. They can be found in sputum, which assists in early detection. This type is more often cured through early detection and surgical removal than the other types. This form of lung cancer is most common in men. It is the slowest growing of the three non-small cell types. Twenty-five to 30 percent of lung cancers are this type.
  
  
• Large cell carcinoma. Cancer cells originating in the peripheral parts or edges of the lungs. These cells are large, grow and spread aggressively to distant organs. This type is more likely to metastasize to the brain. It accounts for 10 to 15 percent of lung cancers.
  
  
• Adenosquamous carcinoma. A mix of adenocarcinoma and squamous cell carcinoma.

All of these types of NSCLC have a strong association with smoking.

The chart below indicates at which stage each type of NSCLC is usually diagnosed, according to the Centers for Disease Control and Prevention (CDC):

This chart reveals that distant metastasis may occur early with adenocarcinoma and large cell cancer. These patients are more likely to have higher stage disease at the time of diagnosis.