Causes of cancer

Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't. Cells are the building blocks of living things. There are multiple causes of cancers, including:

  • Radiation
  • Sunlight
  • Tobacco
  • Certain viruses
  • Benzene

HIV is linked with a number of malignancies, including Kaposi's sarcoma. Prolonged exposure to asbestos fibers is associated with mesothelioma. Certain poisonous mushrooms and aflatoxins (a poison produced by organisms that can grow on peanut plants).

Most forms of cancers are "irregular", and have no origins in heredity.   

However,   there are a number of recognized syndromes of cancer with         hereditary elements. The other risk occurs to individuals who have developed cancer from tumors hiding inside organ transplants.   

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