Skin cancer is the most common form of cancer in the United States, but avoiding over exposure to harmful ultraviolet light can prevent it.  More than one million cases of skin cancer are diagnosed each year in the U.S. Skin cancer is primarily caused by over exposure to the ultraviolet rays of the sun as well as from exposure in tanning salons.

It maybe the result of a very bad sunburn years ago or from an accumulation of sun exposure over many years.  Dr. Stephen Stone, professor of dermatology at SIU School of Medicine, explains the types of skin cancer.

Click here for Stone's comments

Dr. Stone says a melanoma is black, brown or a combination of various dark colors and usually has an irregular shape. It should be removed as soon as possible.

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