Non-small cell lung cancer (NSCLC) gets its name from how the cancer cells look under a microscope.
Lung cancers are broadly divided into two main groups: small cell lung cancer and non-small cell lung cancer. When looking at the tumor cells under a microscope, small cell lung cancer has very small, tightly packed cells that look different and tend to grow and spread quickly. In contrast, non-small cell lung cancer includes cancers whose cells are larger and appear more varied in shape and structure. There are several subtypes of non-small cell lung cancer.
Each type of non-small cell lung cancer has different kinds of cancer cells. The cancer cells of each type grow and spread in different ways. The types of non-small cell lung cancer are named for the kinds of cells found in the cancer and how the cells look under a microscope:
- Squamous cell carcinoma: Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. This is also called epidermoid carcinoma.
- Large cell carcinoma: Cancer that may begin in several types of large cells.
- Adenocarcinoma: Cancer that begins in the cells that line the alveoli and make substances such as mucus.
Other less common types of non-small cell lung cancer are: pleomorphic, carcinoid tumor, salivary gland carcinoma, and unclassified carcinoma.
Smoking increases the risk of developing non-small cell lung cancer. However, non-smokers can also develop this type of cancer.
Learn more about diagnosing non-small cell lung cancer.
