Lung cancer is a disease in which cancer cells grow in the lungs. There are two types of lung cancers:

  • Non-small cell lung cancer—generally grows and spreads more slowly (more common form)
  • Small cell lung cancer—generally grows more quickly and is more likely to spread to other parts of the body

Lung cancer is the leading cause of cancer deaths in the United States for both men and women.

Lung Cancer
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Cancer occurs when cells in the body divide without control or order. Normally, cells divide in a regulated manner. If cells keep dividing uncontrollably when new cells are not needed, a mass of tissue forms, called a growth or tumor. The term cancer refers to malignant growths. These growths can invade nearby tissues. Cancer that has invaded nearby tissues can then spread to other parts of the body.

The following can cause damage to the cells in the lungs, leading to lung cancer:

  • First- or second-hand smoke from cigarettes, cigars, or pipes
  • Exposure to asbestos (a type of mineral) or radon (radioactive gas)