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Skin Cancer - Description

basal cell carcinomaSkin cancer is a disease in which cancerous cells grow in the outer layers of a person's skin. For example, the tumor shown here is an untreated basal cell carcinoma occupying a good portion of the right temple.

Skin cancer is the most common type of cancer in the United States. In fact, an estimated 2 in every 5 Americans who reach the age of 65 will develop skin cancer sometime in their lives.

Skin cancer is the most curable form of cancer, almost 100 percent if it is caught early. Treatment involves removing or destroying the tumor completely while causing minimal damage to surrounding tissues.

Skin cancer also is one of the most preventable cancers. Some scientists have estimated that 90-95 percent of all cases result from overexposure to the sun and might have been avoided if the patients had practiced appropriate protective measures.

Skin Cancer - Detection

The cure rate for skin cancer could be 100 percent if all skin cancers were brought to a doctor's attention before they had a chance to spread. Therefore, people should check themselves regularly for new growths or other changes in the skin. Any new, colored growths or any changes in growths that are already present should be reported to a doctor without delay.

Doctors also should look at the skin during routine physical exams. People who have already had skin cancer should be sure to have regular exams so that the doctor can check the skin, both the treated areas and other places where cancer may develop.

microscopeSkin Cancer - Diagnosis

Most skin cancer is 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.

Doctors generally divide skin cancer into two stages: local (affecting only the skin) or metastatic (spreading beyond the skin). Because skin cancer rarely spreads, a biopsy often is the only test needed to determine the stage. In cases where the growth is very large or has been present for a long time, the doctor will carefully check the lymph nodes in the area. In addition, the patient may need to have additional tests, such as special X-rays, to find out whether the cancer has spread to other parts of the body. Knowing the stage of a skin cancer helps the doctor plan the best treatment.

Skin Cancer - Occurrence

tennis playerSkin cancer is the most common type of cancer in the United States, making up approximately one-half of all types of localized cancer. According to current estimates, 40-50 percent of Americans who live to age 65 will have skin cancer at least once.

The American Cancer Society estimates that in 1998 there were approximately 1 million new cases of highly curable basal cell or squamous skin cancers. The society also estimates that in 1998 more than 40,000 new cases of melanoma, the most serious form of skin cancer, were diagnosed. The incidence of melanoma is approximately 20 times higher among Caucasians than among African Americans.

Skin Cancer - Prevention (Personal Actions)

The best defense against skin cancer is protection from the sun and ultraviolet light.

The National Cancer Institute recommends that 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 savings time). People should remember that protective clothing, such as sun hats and long sleeves, can block out the sun's harmful rays. Also, lotions that contain sunscreen with an SPF of 15 or higher can protect the skin.

children at the beachThe American Cancer Society notes that there is a link between severe sunburns in childhood and significantly increased risk of developing melanoma later in life. Therefore, children especially should be protected from the sun. In fact, programs promoting behavioral change have begun in U.S. schools and at beaches and pools. Some programs try to teach children with simple messages. For example, the "shadow rule" ("Short shadow! Seek shade!") teaches children that when their shadows are shorter than they are, it is time to seek shade and use sunscreen and hats. Other awareness programs are directed at parents and caregivers.

Additional prevention tips from the American Academy of Dermatologists include:

poster of two teenagers popping out of a toaster. Title reads: If You're Tanned, You're ToastSkin Cancer - Prevention (Societal Actions)

Many organizations, including the National Cancer Institute, the American Cancer Society, and the American Academy of Dermatologists (AAD) distribute educational programs that alert the public to risk factors associated with skin cancer and ways to detect and prevent the disease. For example, in 1998 the Centers for Disease Control and Prevention (CDC) launched "Choose Your Cover," the federal government's first national sun-protection initiative. The five-year program will use media announcements to influence the public's perceptions about sun protection and suntanning. The initiative's ultimate goal is to increase people's willingness and tendency to practice sun-safe behaviors.

Many organizations also produce materials that encourage health care professionals to regularly examine their patients' skin for signs of cancer and improve their ability to detect it at an early stage. Currently, only an estimated 14-25 percent of melanoma is discovered by a physician prior to the patient noticing something wrong.

Some organizations offer free skin examinations by dermatologists. One program sponsored by AAD provided free screening to almost 750,000 Americans between 1985 and 1994. These programs have shown some success. For example, of 195,660 people screened from 1992 to 1993, at least 261 cases of melanoma were confirmed in 257 individuals. Based on comments from these people, an estimated 36 percent of those with confirmed cases would not have seen a physician if the screening had not been available.

To promote public awareness of the hazards of ultraviolet light, the United States Weather Service, the Environmental Protection Agency, and the CDC publicize the UV index in television and newspaper weather reports in more than 50 major cities across the nation. This index rates predicted UV intensity on a scale of 1 to 10+ and suggests appropriate protective measures.

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