Biology and You

You and Your Body

What is cancer?

Cancer is caused by the unrestrained growth of cells. Cells that do not “follow the rules” of normal cell cycling may eventually become cancerous. This means that the cells reproduce more often than normal, creating tumors. Usually this happens over an extended period of time and begins with changes at the molecular level. More than one hundred distinct types of cancer exist, each of which behaves in a specific fashion and responds to treatment differently.


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