Understanding Your Type of Lung Cancer

Microscopic image of lung carcinoma.

There are two main types of lung cancer. They are non-small cell lung cancer and small- cell lung cancer. A doctor called a pathologist uses a microscope to look at the cancer cells collected during your biopsy to tell which type of cancer you have. These two types of lung cancer grow and spread in different ways. Therefore, they are treated differently. Non-small cell lung cancer usually grows and spreads more slowly than small cell lung cancer. 

Non-Small Cell Lung Cancer (NSCLC)

About 85% of lung cancers are non-small cell. There are three kinds of this type of lung cancer.

• Adenocarcinoma. This is the most common kind of non-small cell lung cancer. And it's the most common type of lung cancer in nonsmokers. It rarely shows symptoms in the early stages before it has spread beyond the lung and nearby lymph nodes. It tends to grow in the outer edges of your lungs and in cells that coat your respiratory system with fat.

• Squamous cell carcinoma (epidermoid carcinoma). This type of non-small cell lung cancer tends to spread more slowly than adenocarcinoma or large cell. It develops more often in men than women. It's sometimes easier to find than other types of non-small lung cancer because the cancer cells are shed in mucus and can be coughed up. So a test of your coughed-up mucus, called a sputum test, can find this cancer. The cancer cells are also found in the cells that line your lungs. These cancers tend to start in the middle part of the lungs.

• Large cell. This is the least common of the three kinds of non-small cell lung cancer. It may spread early to other organs.

Small Cell Lung Cancer (SCLC)

Only about 15% of people diagnosed with lung cancer get small cell lung cancer. Small cell lung cancer is also called oat cell cancer. It grows and spreads more quickly than non-small cell lung cancer. It often spreads to other parts of the body at an early stage. This type of cancer is almost always associated with smokers. If you don't smoke, you aren't likely to get small cell lung cancer.