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Overview of Skin Cancer


Gregory L. Wells

, MD, Ada West Dermatology and Dermatopathology

Reviewed/Revised Sep 2022
Topic Resources

Skin cancer is the most common type of cancer. Skin cancer is most common among people who work or play sports outside and among sunbathers. Fair-skinned people are particularly susceptible to developing most forms of skin cancer because they produce less melanin. Melanin, the protective pigment in the outer layer of skin (epidermis), helps protect the skin from ultraviolet (UV) light. However, skin cancer also can develop in dark-skinned people and in people whose skin has not had significant sun exposure. Skin cancers may also develop years after x-ray therapy or exposure to substances that cause cancer (for example, ingestion of arsenic).

Over 5.4 million new cases of nonmelanoma skin cancer were diagnosed in 2012 among over 3.3 million people in the United States.

The three main types of skin cancer are

These three types are caused, at least in part, by long-term sun exposure.

Less common types of skin cancer are

Most skin cancers are curable, especially when treated at an early stage. At first, skin cancers do not cause any symptoms. Therefore, any unusual skin growth that enlarges or lasts for more than a few weeks should be examined by a doctor.

Skin Cancer

Screening for skin cancer

People should notify their doctor if they notice any unusual or changed skin marks. Routine skin examination is done by doctors or by people examining their own skin, or both.

Prevention of skin cancer

Because many skin cancers seem to be related to UV exposure, doctors recommend a number of measures to limit UV exposure, starting in early childhood.

Did You Know...

  • Most skin cancers are caused, at least in part, by spending a lot of time in the sun.

Treatment of skin cancer

Doctors treat most skin cancers by removing them surgically. Usually, the scar that is left after surgery depends on the size of the original cancer, which, if caught early, may be small.

Larger or more invasive cancer may require removal of a significant amount of skin, which may have to be replaced with a skin graft or a skin flap.

With a skin graft Skin Tissue transplantation is the removal of various tissues, such as skin cells, corneas, cartilage, or bone, from a body and then inserting that tissue into the same or another person who has... read more , a piece of skin is removed from another area of the person's body, typically where the skin is loose. The piece of skin is sewn onto the area where the cancer was removed.

With a skin flap, doctors transfer skin from an adjacent area to replace the area where the cancer was removed. With a flap, but not with a graft, the transferred skin is not cut completely free, so it still has its own blood supply. Also, a flap is usually thicker than a graft.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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