Lung Cancer - Small Cell

Lung cancer affects more than 200,000 Americans each year. About 10% to 15% of people with lung cancer have small cell lung cancer. Although cigarette smoking is the main cause of lung cancer, anyone can develop the disease. Lung cancer is treatable, no matter the size, location, whether the cancer has spread, and how far it has spread.

Because lung cancer is associated with smoking, patients may feel that they will not receive as much support or help from people around them because they believe that others will think that their behavior caused the disease. The truth is that most smokers do not develop lung cancer, and not all people diagnosed with lung cancer smoke. Lung cancer is a disease that can affect anyone. In fact, most people who get lung cancer today have either stopped smoking years earlier or never smoked.

About the lungs

When a person inhales, the lungs absorb oxygen from the air and bring the oxygen into the bloodstream for delivery to the rest of the body. As the body’s cells use oxygen, they release carbon dioxide. The bloodstream carries carbon dioxide back to the lungs, and the carbon dioxide leaves the body when a person exhales. The lungs contain many different types of cells. Most cells in the lung are epithelial cells. Epithelial cells line the airways and make mucus, which lubricates and protects the lung. The lung also contains nerve cells, hormone-producing cells, blood cells, and structural or supporting cells.

About small cell lung cancer

There are two main classifications of lung cancer: small cell lung cancer and non-small cell lung cancer (NSCLC). These two types are treated differently. This guide provides information on small cell lung cancer. Learn more about NSCLC.

Small cell lung cancer begins when healthy cells in the lung change and grow uncontrollably, forming a mass called a tumor, a lesion, or a nodule. Small cell lung cancer begins in the nerve cells or hormone-producing cells of the lung. The term “small cell” refers to the size and shape of the cancer cells as seen under a microscope.

A tumor can be cancerous or benign. Once a cancerous lung tumor grows, it may or may not shed cancer cells. These cells can be carried away in blood or float away in the fluid, called lymph, that surrounds lung tissue. Lymph flows through tubes called lymphatic vessels that drain into collecting stations called lymph nodes, the tiny, bean-shaped organs that help fight infection. Lymph nodes are located in the lungs, the center of the chest, and elsewhere in the body. The natural flow of lymph out of the lungs is toward the center of the chest, which explains why small cell lung cancer often spreads there first. When a cancer cell moves into a lymph node or to a distant part of the body through the bloodstream, it is called metastasis.

Normal lung tissue

Normal lung tissueClick to Enlarge

Lung - Small Cell Cancer

Lung - small cell cancerClick to Enlarge

These images used with permission by the College of American Pathologists.

Looking for More of an Overview?

If you would like additional introductory information, explore these related items. Please note these links will take you to other sections on Cancer.Net:

  • ASCO Answers Fact Sheet: Read a one-page fact sheet (available as a PDF) that offers an easy-to-print introduction to lung cancer.

  • ASCO Answers Guide: This 40-page booklet (available as a PDF) helps newly diagnosed patients better understand their disease and treatment options, as well as keep track of the specifics of their individual cancer care plan.