Skin Cancer Overview

What skin cancer looks like under the microscope. See more pictures of skin problems.
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Warnings about skin cancer seem to come from all sides -- from scientific researchers and family doctors, from parents to children, even from adult children to elderly parents. You may think you already know something about the disease and that you don't spend much time in the sun anyway. But as skin cancer rates continue to rise, greater awareness can help reduce its occurrence and save lives.

Whether a person seeks out the sun or hides in the shade, skin cancer is a real possibility for virtually anyone. It is the most common type of cancer in the United States, affecting more than 1 million people each year [source: American Academy of Dermatology]. Almost half of Americans who live to age 65 will have some form of skin cancer at some point in their lives [souce: National Cancer Institute].

It's important to understand exactly what skin cancer is before discussing the details of the disease. If a person is diagnosed with skin cancer, it means that malignant (life-threatening) cancer cells have been found in the skin's outer layers.

Learning about skin cancer also requires a little knowledge about the structure of the epidermis, the skin's outer layer. The epidermis is made up of three different kinds of cells -- squamous cells, basal cells and melanocytes.

Squamous cells are scaly, flat cells that make up most of the cells in the outer layer. Basal cells are round cells that can be found beneath the squamous cells. Deeper within the epidermis are the melanocytes, which give skin its color [source:] Some types of skin cancers are named for the cells where the cancer is found, such as squamous cell carcinoma.

People who are most at risk of developing skin cancer are those who sunburn easily and are fair-skinned [source: American Academy of Dermatology]. These and other factors relating to skin cancer will be discussed in this article as well as symptoms, preventive measures and treatments. Read on to first learn about the various types of skin cancer.