Types

Cancers that begin in the lungs are divided into two major types - non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) - these names refer to how the cells look under a microscope to a pathologist. Each type grows and spreads in different ways and is treated differently.

Non-small cell lung cancer is the most common and makes up about 80 to 85% of all lung cancers. NCSLC is generally less aggressive than small cell lung cancer. NSCLC is then further divided into sub-types and each is named for the cells in which the cancer develops.

Squamous cell carcinoma (also called epidermoid carcinoma) forms in the lining of the bronchial tubes. It is usually associated with smoking.
Adenocarcinoma is typically found in the glands of the lungs that produce mucus. This is the most common type of lung cancer in women and also among people who have not smoked.
Bronchioalveolar carcinoma is a rare subset of adenocarcinoma. It forms near the lungs' air sacs.
Large-cell undifferentiated carcinoma can form in any part of the lung. It can grow rapidly.

Small cell lung cancer is sometimes called oat cell cancer, oat cell carcinoma, and small cell undifferentiated carcinoma.

Small cell lung cancer is less common than non-small cell and makes up about 15 to 20% of lung cancers. It grows more quickly and is more likely to spread to other organs. Smoking is almost always the cause of SCLC.
Because different types of lung cancer are treated differently, your oncologist along with the rest of your health care team will determine exactly what treatment is best for you. Remember, no matter what type or what stage of lung cancer you have, there are treatment options.