About Skin Cancer

Skin cancer, or uncontrolled division and growth of skin cells, is the most common type of cancer. More than a million cases are diagnosed in the United States each year. Nearly all of these cases can be linked to excessive exposure to the ultraviolet rays of the sun.1  Fortunately, skin cancer is also one of the most curable forms of cancer, if detected and treated early.

Anyone who spends time in the sun without protection is vulnerable. It's important to know how to protect yourself from damaging rays and how to detect suspicious lesions on your skin in the early stages when they can still be treated.

Types of Skin Cancer2

The three most common types of skin cancer are:

Basal Cell Carcinomas

  • Account for 75-80 percent of all skin cancers.
  • Linked to cumulative sun exposure that damages the basal cells.
  • Typically occur in people over 60 who have spent most of their lives outdoors, but are becoming more prevalent in young people, even before age 30.
  • Commonly seen on the ears, face, forehead, neck or other areas getting heavy sun exposure.
  • Might appear as a waxy or pearly lump, a flat pink growth, or a sore that does not heal. These lesions often crust and bleed.
  • Rarely spread, but can damage underlying skin and bones. Should be removed early, but about half of surgically removed lesions will grow back.

Squamous Cell Carcinomas

  • Represent 16 to 19 percent of skin cancers.
  • Linked to cumulative sun exposure that damages the squamous cells.
  • Have a potential to spread to other parts of the body, but are relatively easy to treat if detected early.
  • Often starts as a red, flaky or scabby patch of skin that gradually becomes a raised bump or nodule -- sometimes with bleeding.
  • May also develop from precancerous lesions known as actinic keratoses -- dry, rough, scaly patches appearing on sun-damaged skin. These can usually be treated with topical medications or surgery. Several new treatment options are emerging.


  • The most deadly skin cancer, but also the least common, accounting for only about five percent of skin cancers.
  • Originates in the melanocytes, but if left undetected or untreated, melanoma can metastasize, or spread to other areas of the body.
  • Found most commonly among people living in sunny climates.
  • Incidence is increasing rapidly, doubling over the past 20 years.
  • Link to sun exposure is unclear. May be linked to even one or two severe sunburns suffered in childhood or adolescence, rather than cumulative exposure over a lifetime.
  • Most frequently found on the back or torso for men; on the legs for women. May also appear on areas such as the sole of the foot that are rarely exposed to sun.
  • Easy to overlook, because it may resemble moles or grow out of existing moles.

Protecting Yourself -- A Lifetime Project3

For the average American, 80 percent of lifetime sun exposure comes before age 18, and some of the most deadly cancers are believed to be associated with even one or two bad burns during youth. So sun protection is an important key to prevention, and should be a lifetime project.

  • Shield infants from the sun during their first six months. After that, protect them with sunscreen and clothing every time they go outside.
  • Try to plan activities so that you and your children are not in the sun between 10 a.m. and 4 p.m. (9 a.m. to 3 p.m. daylight savings time.)
  • Wear long sleeves and pants, wide-brimmed hats and sunglasses that provide 100% UV protection.
  • Sunscreen is not just for a day at the beach, but for everyday use. Choose one with a sun protective factor (SPF) of 15 or higher that blocks both UVA and UVB rays. Apply it liberally at least 30 minutes before sun exposure and every two hours thereafter. Keep in mind that UV rays can penetrate water, clouds and even shade.
  • Ears, nose, face, neck and balding areas on the scalp are particularly vulnerable to both overexposure and skin cancer. Don't forget to cover them with sunscreen or a hat.
  • Remember, there's no such thing as a healthy tan. Sunburn is associated with ultraviolet B (UVB) radiation, but scientists now know that ultraviolet A (UVA) is at least as dangerous, particularly to collagen, the fibrous protein that gives skin its youthful appearance. Your tan is a sign that your skin has been damaged and is at risk for premature aging and skin cancer.

Detecting Skin Cancer Early -- Know Your ABCDE's4

The key to successfully treating skin cancer is early detection.  Even melanoma - the most dangerous type of skin cancer - can be cured if it is detected early and properly treated. 

It 's important to do regular self-examinations, so you can become aware of all the moles and other growths on your skin, and make note of any changes. The formula to help identify suspicious lesions, developed by the American Academy of Dermatology, is ABCDE. Use this formula to point out the spots that concern you, and let your doctor check them out. Don't attempt to make your own diagnosis.

  • Asymmetry - Most harmless growths are round or oval and can be divided into symmetrical halves. Irregular shapes or sizes are more likely to spell trouble.
  • Border - Growths with vaguely defined borders need to be checked out. B is also for bleeding: A mole shouldn't bleed unless it has been traumatized.
  • Color - Melanomas tend to have many colors within them or unevenly distributed colors -- red, brown, black, blue or white.
  • Diameter - Growths larger in diameter than a pencil eraser (about 6 mm), or moles that are getting bigger, should be checked by a doctor.
  • Elevation - Watch for moles that were formerly flat or only slightly raised, yet have increased rapidly in height.

Diagnosis and Treatment

You should have your doctor check your skin if you:

  • Have a sore that won't heal
  • Find a spot on your skin that has some of the ABCDE characteristics described above
  • Notice sudden changes in spots or moles on your skin.

After examining your skin, your doctor may decide to perform a biopsy - removing a sample of the suspicious tissue for evaluation under a microscope. This biopsy is typically done as a routine office procedure while you are awake.

If the results of your biopsy show that you have skin cancer or pre-cancerous cells, your treatment options will depend on the size, depth and location of the growth; the type of skin cancer; and whether the cancer has spread to other areas of the body. Your family doctor may be able to remove the growth in the office, or he or she may refer you to a specialist. Some common treatment options may include:

  • Electrodesiccation and curettage - Removing the surface of the skin cancer and gently burning or "cauterizing" the underlying base with an electric needle.
  • Simple surgical excision - Cutting out the skin cancer and sewing the skin together using cosmetic surgical techniques.
  • Cryosurgery - Using "freezing" to remove the skin cancer
  • Radiation therapy
  • Laser surgery

In cases where the skin cancer is not very deep, treatment might be performed at the same time as the biopsy. Typically the removed specimen will also be examined under a microscope, to determine that all the skin cancer has been removed.

Keep in mind that once you have skin cancer, you are at increased risk of developing additional skin cancers, so you should continue to do self-examinations and have your doctor closely monitor your skin throughout your life. Your doctor may even recommend a "mole map," as a helpful tool. A mole map provides detailed documentation, usually with drawings or photos, of where all of the normal moles and spots are on your body, so that changes will be easier to detect.


1Sun Rays: A Major Health Hazard Today, Kenneth Jones, Ph.D. and G. Adolph Ackerman, M.D., Ph.D. of Ohio State University, 1997, The Skin Cancer Foundation.

2Skin Cancer Alert, April 2002, Healthwire.

3Simple Steps to Sun Safety, Medical Reviewers: Leonard Goldberg, M.D. and Warwick L. Morison, M.D, 2003, The Skin Cancer Foundation.

4The ABCDE's of Skin Cancer, 2003, American Academy of Dermatology. 

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