What is small cell lung cancer?

Small cell lung cancer is fast-growing lung cancer that develops in the tissues of the lungs. By the time a person gets a diagnosis, small cell lung cancer has typically spread (metastasized) outside of the lungs. This cancer is also more likely than other types of lung cancer to come back after treatment. Small cell lung cancer is sometimes, but not often, called oat cell cancer because the small, oval-shaped cells look like oat grains under a microscope.

What are the types of lung cancer?

Small cell lung cancer is the least common type of lung cancer. More people who have lung cancer — an estimated eight out of 10 — develop non-small cell lung cancer (NSCLC). Compared to NSCLC, small cell lung cancer grows faster and is more likely to spread.

What are the types of small cell lung cancer?

There are two types of small cell lung cancer. Cancer cells grow and spread differently depending on the type. Doctors named the types for the kinds of cells in the cancer and how they look under a microscope:

  • Small cell carcinoma.
  • Combined small cell carcinoma.

How common is small cell lung cancer?

An estimated 15% of people diagnosed with lung cancer have small cell lung cancer.

Who might have small cell lung cancer?

Smokers, people with a history of smoking and nonsmokers are all at risk for lung cancer. However, small cell lung cancer almost always develops in people who have a long history of tobacco use.

What causes small cell lung cancer?

While anyone can get lung cancer, current and former smokers are most at risk for small cell lung cancer. Other risk factors include:

  • Secondhand smoke.
  • Radiation exposure via cancer treatments, home radon or diagnostic imaging scans.
  • Family history of lung cancer.
  • Human immunodeficiency virus (HIV).
  • Workplace exposure to asbestos, arsenic, nickel, tar or other chemicals.
  • Air pollution.
  • Advanced age.

What are the symptoms of small cell lung cancer?

Early-stage small cell lung cancer that hasn’t spread rarely causes symptoms. As the disease progresses, you may experience:

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