Skin Cancer Basics

Featured Article, Skin Cancer
on June 8, 2011

What is skin cancer?

Cancer is a disease in which cells become abnormal and form more cells in an uncontrolled way. With skin cancer, the cancer begins in cells that make up the skin. The skin is the body’s largest organ. It protects us against heat, light, injury, and infection. It regulates body temperature and stores water, fat, and vitamin D. With skin cancer, new cells form when the skin does not need them, and old cells do not die when they should. These extra cells form a mass of tissue called a tumor. Not all tumors are cancer. Tumors that are cancer can invade and damage nearby tissues and organs, and sometimes can spread to other parts of the body.

Skin cancers are named for the type of cells where the cancer starts. The three types are:

  • Basal cell carcinoma— usually occurs on parts of the skin that have been in the sun a lot, such as the face. It is slow-growing and rarely spreads to other parts of the body.
  • Squamous cell carcinoma— also occurs on parts of the skin that have been in the sun. But also can be found on parts of the skin not exposed to the sun. This type sometimes spreads to other organs inside the body.
  • Melanoma— the most serious type, this skin cancer is likely to spread to other parts of the body if not caught and treated early. It is much less common than the other types.

Why should I be concerned about skin cancer?

Skin cancer is the most common type of cancer in the United States. About one million Americans get it each year. The number of new cases of skin cancer appears to be rising each year. The number of deaths due to skin cancer, though, is fairly small. The good news is that skin cancer is now almost 100 percent curable if found early and treated promptly.

Ultraviolet (UV) radiation from the sun is the main cause of skin cancer. Other sources of UV radiation, such as sunlamps and tanning booths, also can cause skin cancer. Although anyone can get skin cancer, the risk is greatest for people who have:

  • skin that tans poorly or burns easily
  • a large number of moles, especially abnormal moles

Most skin cancers appear after age 50. But the sun’s damaging effects begin at an early age. So, protection should start in childhood to prevent skin cancer later in life.

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