Skin Cancer

Skin cancer is the most common type of cancer, affecting hundreds of thousands of people each year. Skin cancer occurs in the outer layers of the skin. People who have light-colored skin and those who have spent a lot of time in the sun are most at risk. Because sun exposure is a risk factor for skin cancer, skin cancer is most likely to occur on the face (including the lips and ears), the neck, and the arms.

Skin cancer is classified by the type of skin cells in which it develops: basal cells or squamous cells. A third type, melanoma, develops in the pigment-containing cells deep in the skin. Melanoma is far less common but far more serious than basal or squamous cell cancers. Although the diagnosis and treatment of basal and squamous cell cancers are similar, the approach to melanoma is more complex.

Symptoms and Diagnosis

The earliest sign of skin cancer is a change in the skin. A person may notice a new mole or a change in an existing mole. A smooth, shiny, or waxy looking lump or an area of skin that is red or reddish brown or rough or scaly looking may be a sign of skin cancer. A sore or rash that will not heal is another sign.

Because skin cancer that is found early is usually curable, a person who notices a change in the appearance of his skin should be checked by a doctor. The doctor examines the skin and performs a biopsy. Usually, the biopsy can be done in the doctor's office.

Prevention and Treatment

Skin cancer most often results from many years of exposure to the sun, but it is never too late to protect the skin. People should use sunscreens with a high skin protection factor (SPF) on all exposed areas of the skin when they are outside. Wearing long-sleeved shirts, long pants, and wide-brimmed hats is also helpful.

People should examine their skin about every 3 to 4 months, and they should be examined by a doctor if they notice changes. Because it is difficult to see all areas of the skin, especially if movement is hampered by some other condition (such as arthritis), a family member should be asked to examine hard-to-see areas. Older people should have all areas of their skin examined every year by a doctor.

Sometimes a doctor detects a patch of skin that is likely to become cancerous. The patch is called actinic keratosis. Doctors usually recommend removing actinic keratosis when it is found rather than waiting for cancer to develop. To remove actinic keratosis, a doctor may apply liquid nitrogen or a chemical.

Treatment of skin cancer depends on the type, location, and extent of the cancer, as well as the person's general health. Most often, a skin cancer is removed with surgery, along with some of the skin around it. For melanomas, a wider area of tissue must be removed, and nearby lymph nodes must also be examined for evidence of spread.

The person may have a scar after the cancer is removed. In some areas, such as the face, the surgery is done using a microscope (Mohs' surgery) to minimize the amount of tissue removed. If a large area of tissue is removed, a skin graft may be used to help the site heal. In a skin graft, healthy tissue from another area of the body is used to cover the site from which the cancer was removed. Sometimes additional surgery can be performed after the area has healed to improve the appearance of the scar.

Skin cancer in some sites may be treated with radiation therapy.

Outlook

Most basal cell and squamous cell skin cancers can be cured but, if left until late, can cause significant disfigurement. Melanomas are curable if treated early but are often fatal if not. People treated for skin cancer should be re-examined by a doctor regularly so that cancer can be detected early if it returns.