National Cancer Institute
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Science Behind the News Understanding Cancer
 
A drawing of the skin. When basal cells divide faster than needed and do not die, they accumulate and displace normal cells.

The Beginning of Cancerous Growth

During the development of skin cancer, the normal balance between cell division and cell loss is disrupted. The basal cells now divide faster than is needed to replenish the cells being shed from the surface of the skin. Each time one of these basal cells divides, the two newly formed cells will often retain the capacity to divide, thereby leading to an increase in the total number of dividing cells.



 
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