Skin Cancer

Every year nearly one million people in the United States learn that they have skin cancer according to the National Cancer Institute. Skin cancer is the most common type of cancer in the United States, Australia and South Africa. Skin cancer is the most common type of cancer in both men and women.

The two most common kinds of skin cancer are basal cell carcinoma and squamous cell carcinoma. (Carcinoma is cancer that begins in the cells that cover or line an organ.) Basal cell carcinoma accounts for more than 90 percent of all skin cancers in the United States. It's a slow growing cancer that seldom spreads to other parts of the body.

Squamous cell carcinoma also rarely spreads, but it does more often than basal cell carcinoma. It is important that skin cancers be found and treated early because they can invade and destroy nearby tissue. Basal Cell Carcinoma occurs from sun exposure and it occurs occurs many years after exposure.

Another type of cancer that occurs in the skin is melanoma, which begins in the melanocytes.

Cause and Prevention

Although anyone can get skin cancer, the risk is greatest for people who have fair skin that freckles easily -- often those with red or blonde hair and blue or light-colored eyes.

Ultraviolet (UV) radiation from the sun is the main cause of skin cancer. (Two types of ultraviolet radiation -- UVA and UVB. Artificial sources of UV radiation, such as sun lamps and tanning booths, tanning beds can also cause skin cancer.

The risk of developing skin cancer is affected by where a person lives. People who live in areas that get high levels of UV radiation from the sun are more likely to get skin cancer. In the United States, for example, skin cancer is more common in Texas than it is in Minnesota, where the sun is not as strong. Worldwide, the highest rates of skin cancer are found in South Africa and Australia, areas that receive high amounts of UV radiation.

In addition, skin cancer is related to lifetime exposure to UV radiation. Most skin cancers appear after age 45, but the sun's damaging effects begin at an early age. So, protection should start in childhood to prevent skin cancer later in life.

Whenever possible, people should avoid exposure to the midday sun (from 10 a.m. to 2 p.m. standard time, or from 11 a.m. to 3 p.m. daylight saving time). Keep in mind that protective clothing, such as sun hats and long sleeves, can block out the sun's harmful rays. Also, lotions that contain sunscreens can protect the skin. Sunscreens are rated in strength according to a sun protection factor (SPF), which ranges from 2 to 30 or higher. Those rated 15 to 30 block most of the sun's harmful rays.

Symptoms

The most common warning sign of skin cancer is a change on the skin, especially a new growth or a sore that doesn't heal. Skin cancers don't all look the same. For example, the cancer may start as a small, smooth, shiny, pale, or waxy lump. Or it can appear as a firm red lump. Sometimes, the lump bleeds or develops a crust. Skin cancer can also start as a flat, red spot that is rough, dry, or scaly. (Photos - courtesy of the National Cancer Institute)

Both basal and squamous cell cancers are found mainly on areas of the skin that are exposed to the sun -- the head, face, neck, hands, and arms. However, skin cancer can occur anywhere. Don't wait for something on your skin to hurt as skin cancer rarely causes pain.

Diagnosis

Basal cell carcinoma and squamous cell carcinoma are generally diagnosed and treated in the same way. When an area of skin does not look normal, the doctor may remove all or part of the growth. This is called a biopsy. To check for cancer cells, the tissue is examined under a microscope by a pathologist or a dermatologist. A biopsy is the only sure way to tell if the problem is cancer.

Treatment

In treating skin cancer, the doctor's main goal is to remove or destroy the cancer completely with as small a scar as possible. To plan the best treatment for each patient, the doctor considers the location and size of the cancer, the risk of scarring, and the person's age, general health, and medical history. Doctors commonly use a type of surgery called curettage. After a local anesthetic numbs the area, the cancer is scooped out with a curette, an instrument with a sharp, spoon-shaped end. The area is also treated by electrodesiccation. An electric current from a special machine is used to control bleeding and kill any cancer cells remaining around the edge of the wound. Most patients develop a flat, white scar.

Cryosurgery

Extreme cold may be used to treat pre-cancerous skin conditions, such as actinic keratosis, as well as certain small skin cancers. In cryosurgery, liquid nitrogen is applied to the growth to freeze and kill the abnormal cells. After the area thaws, the dead tissue falls off. More than one freezing may be needed to remove the growth completely. Cryosurgery usually does not hurt too much and patients may have pain and swelling after the area thaws. A white scar may form in the treated area.

Laser Therapy

Laser therapy uses a narrow beam of light to remove or destroy cancer cells. This approach is sometimes used for cancers that involve only the outer layer of skin.