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Skin Cancer

What is skin cancer?

Skin cancer is a malignant tumor that grows in the skin cells and strikes more people worldwide than any other form of cancer. In the US alone, more than one million Americans will be diagnosed with the disease this year, according to the Centers for Disease Control and Prevention (CDC).

What are the different types of skin cancer?

There are three main types of skin cancer, including:

Name	Description
basal cell carcinoma	Basal cell carcinoma accounts for approximately 75 percent of all skin cancers. This highly treatable cancer starts in the basal cell layer of the epidermis (the top layer of skin) and grows very slowly. Basal cell carcinoma usually appears as a small, shiny bump or nodule on the skin - mainly those areas exposed to the sun, such as the head, neck, arms, hands, and face. It commonly occurs among persons with light-colored eyes, hair, and complexion.
squamous cell carcinoma	Squamous cell carcinoma accounts for about 20 percent of all skin cancer cases. Although more aggressive than basal cell carcinoma, this cancer is highly treatable. Squamous cell carcinoma may appear as nodules or red, scaly patches of skin, and may be found on the face, ears, lips, and mouth. However, squamous cell carcinoma can spread to other parts of the body. This type of skin cancer is usually found in fair-skinned people.
malignant melanoma	Although less common, this type of skin cancer is the most deadly, accounting for approximately 79 percent of all skin cancer deaths. Malignant melanoma starts in the melanocytes - cells that produce pigment in the skin. Malignant melanomas usually begin as a mole that then turns cancerous. This cancer may spread quickly. Malignant melanoma most often appears on fair-skinned men and women, but persons with all skin types may be affected.

Distinguishing benign moles from melanoma:

To prevent melanoma, it is important to examine your skin on a regular basis, and become familiar with moles, and other skin conditions, in order to better identify changes. According to recent research, certain moles are at higher risk for changing into malignant melanoma. Moles that are present at birth, and atypical moles, have a greater chance of becoming malignant. Recognizing changes in moles, by following this ABCD Chart, is crucial in detecting malignant melanoma at its earliest stage. The warning signs are

Asymmetry: half of the mole does not match the other half

Border: the border (edges) of the mole are ragged or irregular

Color: the color of the mole varies throughout

Diameter: moles with a diameter larger than a pencil's eraser

Melanomas vary greatly in appearance. Some melanomas may show all of the ABCD characteristics, while other may only show changes in one or two characteristics. Always consult your physician for a diagnosis.

What are the causes and risk factors for melanoma?

Skin Type
Skin cancer is more common in fair-skinned people – especially those with blond or red hair, who have light-colored eyes. However, no one is safe from skin cancer.

Tanning
Tanning is the skin's response to ultraviolet (UV) light - a protective reaction to prevent further injury to the skin from the sun. However, tanning does not prevent skin cancer.

Heredity
People with a family history of skin cancer are generally at a higher risk of developing the disease. People with fair skin and a northern European heritage appear to be most susceptible.

Environment
Due to a reduction of ozone in the earth's atmosphere, the level of UV light today is higher than it was 50 or 100 years ago. Ozone serves as a filter to screen out and reduce the amount of UV light that we are exposed to. With less atmospheric ozone, a higher level of UV light reaches the earth's surface.

Other factors that contribute to skin cancer:

• multiple nevi (moles) or atypical moles

• exposure to coal and arsenic compounds

• elevation
  Ultraviolet light is stronger as elevation increases (because the thinner atmosphere at higher altitudes cannot filter UV as effectively as it does at sea level).

• latitude
  The rays of the sun are strongest near the equator.

• repeated exposure to x-rays

• scars from disease and burns