Skin cancer develops in the cells in your skin. Normally, these cells go through a growth cycle in which old cells die and are pushed out by new cells continuously. In skin cancer, the DNA that controls that growth cycle is damaged, most commonly by ultraviolet radiation from the sun. This causes an overgrowth of cells, which eventually builds up and forms a tumor. The type of skin cancer you have depends on the type of cell that is affected, but all types of skin cancer begin in the epidermis (the topmost layer of skin).
The main cause of skin cancer is being exposed to ultraviolet (UV) rays from the sun. Warm summer weather often means taking part in more outdoor activities. While it’s important to take opportunities to be more active, when it comes to being out in the sun, people should be sure to take care of their skin.
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Skin cancer is caused by changes in certain types of cells in the skin. Watch Chrysalyne Schmults, MD, Dermatologist at Brigham and Women's Hospital discuss how these cells develop into basal cell carcinoma, squamous cell carcinoma or melanoma.
Ultraviolet (UV) radiation from sunlight is the main cause of skin cancer -- the most common type of cancer in the United States. About one in five Americans develops skin cancer during his or her lifetime.
Continue Learning about Skin Cancer Causes & Risk Factors
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