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Listen to the Cancer.Net Podcast: Protecting Your Skin From the Sun, adapted from this feature.
The warmer weather of summer often means more time spent outdoors in the sun. During the summer—and throughout the year—remember the importance of limiting sun exposure to prevent skin cancer. Although skin cancer is the most common of all cancers, most types of skin cancer can be prevented by reducing exposure to ultraviolet (UV) radiation from sunlight.
Types of skin cancer
There are three main types of skin cancer, which are named after the cells in which each begins.
Basal cell carcinoma (BCC). This is the most common type of skin cancer. The basal cells lie at the bottom of the epidermis, which is the outer layer of skin.
Because BCC is linked with sun exposure, it is usually found on areas of the skin that receive the most sun, such as the face, ears, neck, scalp, shoulders, and back. It may appear as an open sore that bleeds or oozes; a reddish, raised patch or irritated area that may crust or itch; a shiny pink, red, pearly white, or translucent bump; a pinkish growth with an elevated border and crusted central indentation; or a scar-like, white, yellow, or waxy area, often with a poorly defined border.
Squamous cell carcinoma (SCC). This is the second most common type of skin cancer. Squamous cells are flat, scale-like cells that make up most of the epidermis.
Although SCC can start in any area of the body, it is most common in areas that are exposed to the sun. It may crust and bleed and appear as a wart-like growth; a persistent, scaly red patch with irregular borders; an open sore that persists for weeks; or an elevated growth with a rough surface and a central depression.
This type of skin cancer can invade underlying structures if it is not treated and may cause serious health problems or even death.
The American Cancer Society reports that more than 2 million basal cell and squamous cell carcinomas are diagnosed each year in the United States.
Melanoma. This is the most serious type of skin cancer. It can be successfully treated in almost all cases if it is found early. However, melanoma can spread to other parts of the body and is often difficult to treat successfully at later stages. More than 70,000 people in the United States are diagnosed with melanoma each year.
Melanoma is a malignant (cancerous) tumor arising from the melanocytes, which are the cells that produce melanin, the pigment in the skin. It can occur on any area of skin, even on parts of the body that are not exposed to the sun, but it is most commonly found on the backs of men and women and on the legs of women. Melanoma may appear in number of different ways:
- A new, possibly large, irregularly shaped, dark brownish spot with darker or black areas
- A simple mole that changes in color (particularly turning darker), size (growing), or texture (becoming firmer), and/or flakes or bleeds
- An unusual lesion with an irregular border and red, white, blue, gray, or bluish-black areas or spots
- Shiny, firm, dome-shaped bumps that are new, changing, or unusual anywhere on the body
- Dark lesions under the fingernails or toenails; on the palms, soles, or tips of fingers and toes; or on mucous membranes (skin that lines the mouth, nose, vagina, and anus)
Skin cancer occurs more often in people with higher lifetime exposure to the sun or other sources of UV radiation.
People with fair skin—which has less pigment (melanin)—have poorer protection against UV radiation; those with light hair and light-colored eyes who have skin that tans poorly or freckles, or those who burn easily, are more likely to develop skin cancer. This is because skin that has been burned, sunburned, or injured from disease has a higher risk of developing skin cancer.
Sun protection tips
Since most skin cancer is caused by sun exposure, limiting the amount of sun exposure to the skin is the best way to prevent it.
- Use a broad spectrum sunscreen with a sun protection factor (SPF) of 15 or higher every day. Apply it liberally 15 to 30 minutes before going outdoors, and reapply it every two hours, or more often after swimming or heavy sweating.
- Use extra caution near water, snow, and sand; they reflect the damaging rays of the sun, which can increase the chance of sunburn.
- Limit sun exposure between 10:00 AM and 4:00 PM, when the sun's rays are the most intense. Practice the shadow rule: if your shadow is shorter than you, the sun's rays are at their strongest, and you should find shade.
- Protect your skin with a long-sleeved shirt, long pants, and a hat that shades the face, neck, and ears. Dark clothing with tightly woven fabric blocks more sun than white or loosely woven fabrics. For additional protection, look for clothing made with special sun-protective materials.
- Wear sunglasses with 99% to 100% UV absorption to provide optimal protection for the eyes and the surrounding skin.
- Pay attention to the UV index, which is often included in the weather report. This index is a relative measure of how damaging exposure to the sun will be on any particular day. The index is a scale of 1 to 11+. When the index is 11 or higher, people should stay indoors, if possible.
- Avoid tanning beds or sunlamps.
Regular self-examinations of the skin may help find skin cancer early. Examinations should be performed in front of a full-length mirror in a brightly lit room. It helps to have another person check the scalp and back of the neck.
With melanoma, the first sign is often a change in the size, shape, or color of an existing mole. It also may appear as a new or abnormal-looking mole. Most moles are not cancerous, but if you notice a mole that is changing, have it checked by a dermatologist. The "ABCDE" rule can help you remember warning signs.
Asymmetry: The shape of one half of the mole does not match the other.
Border: The edges are ragged, notched, or blurred.
Color: The color is often uneven with shades of black, brown, and tan. You may also see areas of white, gray, red, or blue.
Diameter: The diameter is usually larger than six millimeters (mm) (the size of a pencil eraser) or has grown in size.
Evolving: The mole has been changing in size, shape, color, appearance, or growing in an area of previously normal skin. Also, when melanoma develops in an existing mole, the texture of the mole may change and become hard, lumpy, or scaly. Although the skin may feel different and may itch, ooze, or bleed, melanoma usually does not cause pain.
Meanwhile, people at high risk for skin cancer should have their skin examined once a year by a dermatologist. If detected early, most skin cancer can be treated successfully.
Last Updated: August 29, 2011