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Lung cancer: What is it?

  • Lung cancer starts in the lungs. It is a tumor of abnormal cells that reproduce rapidly and do not grow into normal lung tissue. A lung cancer tumor can grow in one or both lungs.

    There are two main types of lung cancer.

    expand to learn more Non-small cell lung cancer is the most common lung cancer.

    expand to learn more Small cell lung cancer is a fast-growing lung cancer.

  • Malignant mesothelioma is a cancer that involves the lining of the lung. Although it occurs in the chest, it is not considered a form of lung cancer.

    Lung cancer facts

    • Lung cancer causes more deaths than any other type of cancer.
    • Lung cancer is the most preventable type of cancer.
    • To prevent most lung cancer cases, all you need to do is stop smoking—or never start.

    Get more lung cancer facts from our health encyclopedia.