Re: Do normal cells move to other parts of the body, like cancer cells?

 In embryos and youngsters, there is a considerable amount of cell movement 
in the process of tissue formation, but most normal cells in adults do not 
move around to any great extent. Blood cells are an exception. Movement 
through the blood stream is passive. However, lymphocytes and other white 
blood cells leave the circulation and penetrate tissues under some 
circumstances, such as in response to an infection. In fact, there is 
constant movement of the white cells as they perform a function called 
immune surveillance, whereby they seek out invading pathogens and abnormal 
"non-self" cells such as cancer cells. The process immune infiltration of 
tissues is called extravasation and is outlined at these sites:
 http://nic.savba.sk/logos/books/scientific/node38.html
 http://hsc.virginia.edu/medicine/basic-sci/biomed/ley/main.html

Tumor cell metastasis requires similar events to cross the endothelial cell 
barrier that lines blood vessels.