What Are the Types of Lung Cancer?

There are two main types of lung cancer: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). A third less common type of lung cancer is called carcinoid.

Small Cell Lung Cancer (SCLC)

There are two different types of small cell lung cancer: small cell carcinoma and mixed small cell/large cell cancer or combined small cell lung cancer. The types of small cell lung cancer are named for the kinds of cells found in the cancer and how the cells look when viewed under a microscope. Small cell lung cancer is almost always associated with cigarette smoking. Small cell lung cancer is usually treated with chemotherapy.

Non-Small Cell Lung Cancer (NSCLC)

Non-small cell lung cancer is more common. It makes up about 80 percent of lung cancer cases. This type of cancer usually grows and spreads to other parts of the body more slowly than small cell lung cancer does. There are three different types of non-small cell lung cancer:

1. Adenocarcinoma: A form of non-small cell lung cancer often found in an outer area of the lung. It develops in the cells of epithelial tissues, which line the cavities and surfaces of the body and form glands.
2. Squamous cell carcinoma: A form of non-small cell lung cancer usually found in the center of the lung next to an air tube (bronchus).
3. Large cell carcinoma: A form of non-small cell lung cancer that can occur in any part of the lung and tends to grow and spread faster than adenocarcinoma or squamous cell carcinoma.

The above subtypes are the most common, but when your lung cancer tumor is looked at under a microscope, it might reveal even more specific information about the subtype. Work with your doctor to understand exactly which type of lung cancer you have and what it means for your treatment options.