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Skin cancer 101
Some basics about the most common form of cancer in the United States.
Skin cancer occurs when cells in the skin change and grow out of control, producing tumors. There are two types. The most common is nonmelanoma skin cancer. It includes basal cell and squamous cell carcinomas, named for the areas in the outer layer of the skin where they begin.
The most serious type of skin cancer is melanoma. It starts in the melanocytes, the cells that give skin its color. Cases of melanoma are increasing, according to the Skin Cancer Foundation.
Exposure to ultraviolet (UV) radiation from the sun is the main risk factor for most skin cancers, according to the American Cancer Society (ACS). Sunlight is the main source of UV radiation. However, tanning beds also emit UV radiation, and using them has been linked to an increased risk of melanoma and squamous and basal cell carcinomas.
Anyone can get skin cancer. But the risk is higher if you've spent lots of time in the sun or under tanning bed lamps; have had several severe, blistering sunburns, especially as a child or teenager; or live in an area of the country that has year-round bright sunlight, such as a southern climate. People with fair skin and light hair are also at greater risk, as are men. And a weakened immune system; a personal or family history of skin cancer; skin that has been radiated; and exposure to arsenic, industrial tar, coal, paraffin and certain types of oil all increase the risk, according to the ACS and the American Academy of Otolaryngology–Head and Neck Surgery.
Repeated tanning almost certainly will increase your risk. A tan is part of the body's response to sun damage, which causes most skin cancer.
Avoiding ultraviolet light and too much sun is key. Don't sunbathe or use tanning beds or sunlamps. Stay indoors from 10 a.m. to 4 p.m., when the sun is most intense. Before spending time outdoors, protect yourself with long sleeves, a hat with a broad brim, wraparound sunglasses, and sunscreen with a sun protection factor (SPF) of 30 or higher. Use sunscreen even on cloudy days, and reapply every two hours and after swimming or sweating.
You should shield your children from too much sun from the time they are born—and teach them to protect themselves. The risk of skin cancer is related to lifetime UV exposure, and the damage begins early in life.
To find skin cancer early, when it's easiest to treat, perform a skin self-exam monthly. Look for new growths, changes in moles (size, shape, color or texture) or a sore that doesn't heal.
It can also help to think of the "ABCDEs":
- Asymmetry. The growth doesn't look the same on each half.
- Borders. The growth doesn't have smooth edges—they may be scalloped or uneven, for example.
- Color. The growth is not a single color.
- Diameter. The growth is larger in diameter than a pencil eraser.
- Evolving. The growth looks different from others or is changing in size, shape or color.
If you have a growth with any of these traits, have a doctor look at it.
Use a full-length mirror and a hand mirror to check your skin from head to toe, especially moles. Start with your head and face, and check your scalp. Then look at your hands, arms, neck, chest and torso. Use the hand mirror to examine the back of your neck, shoulders, arms, back, buttocks, legs and genitals. Finally, sit down and check the front of your legs and your feet.
The four main treatments for skin cancer are surgery, radiation therapy, chemotherapy and immunotherapy, or biological therapy. Treatment depends on the type of skin cancer and how far it has spread. Surgery is the most common approach.
According to the National Cancer Institute, the chance of recovery from skin cancer depends mostly on the type of cancer and how early it's found. For example, while melanoma accounts for about 1% of skin cancer cases, it causes a large majority of skin cancer deaths, according to the ACS. People who have had one skin cancer have a higher risk of getting another. They should check their skin often to catch any new cancer early. Doctors and family members can help watch for signs of cancer.
To learn more about skin cancer, visit the Skin Cancer health topic center. You can also find out more about skin cancer by visiting these websites: