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Cancer cells can start in any part of the body, but some sites are more favored. Unfortunately these cells rarely remain where they originate. Clusters or clumps of cancer cells break off and travel in the blood stream to other parts of the body – from the breast to the armpits, for example. This spread of cancer cells is called metastasis.
Cancer cells are definitely different from ordinary cells, and these differences can be observed in tiny sections of tissue examined under a microscope. Identifying cancer cells is an important part of the job of the pathologist.
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To identify cancer cells it is necessary to examine …
blood
the breast
the armpits
tissue