What Causes Skin Cancer?
A. Sunburn and Sunlight
Very simply, sunburn and UV light can damage your skin, and this damage can lead to skin cancer. There are of course other determining factors, including your heredity and the environment you live in. However, both the total amount of sun received over the years, and overexposure resulting in sunburn can cause skin cancer. Most people receive 80% of their lifetime exposure to the sun by 18 years of age. The message to parents from this is to protect your children.
Tanning is your skin's response to UV light. It is a protective reaction to prevent further injury to your skin from the sun. However, it does not prevent skin cancer.
Remember, skin cancer is very slow to develop. The sunburn you receive this week may take 20 years or more to become skin cancer.
If there is a history of skin cancer in your family, you are probably at a higher risk. People with fair skin, with a northern European heritage appear to be most susceptible.
The level of UV light today is higher than it was 50 or 100 years ago. This is due to a reduction of ozone in the earth's atmosphere (the Ozone Hole). Ozone serves as a filter to screen out and reduce the amount of UV light that we are exposed to. With less atmospheric ozone, a higher level of UV light reaches the earth's surface.
What is Skin Cancer?
(From the National Cancer Institute PDQ Statement) Skin cancer is a disease in which cancer (malignant) cells are found in the outer layers of your skin. Your skin protects your body against heat, light, infection, and injury. It also stores water, fat, and vitamin D.
The skin has two main layers and several kinds of cells. The top layer of skin is called the epidermis. It contains three kinds of cells: flat, scaly cells on the surface called squamous cells; round cells called basal cells; and cells called melanocytes, which give your skin its color.
A. Basel Cell & Squamous Cell
There are several types of cancer that start in the skin. The most common are basal cell cancer and squamous cell cancer, which are covered in this PDQ patient information statement.
Skin cancer is more common in people with light colored skin who have spent a lot of time in the sunlight. Skin cancer can occur anywhere on your body, but it is most common in places that have been exposed to more sunlight, such as your face, neck, hands, and arms.
Skin cancer can look many different ways. The most common sign of skin cancer is a change on the skin, such as a growth or a sore that won't heal. Sometime there may be a small lump. This lump can be smooth, shiny and waxy looking, or it can be red or reddish brown. Skin cancer may also appear as a flat red spot that is rough or scaly. Not ail changes in your skin are cancer, but you should see your doctor if you notice changes in your skin.
Melanoma is a disease of the skin in which cancer (malignant) cells are found in the cells that color the skin (melanocytes). Melanoma usually occurs in adults, but it may occasionally be found in children and adolescents. Your skin protects your body against heat, light, infection, and injury. It is made up of two main layers: the epidermis (the top layer) and dermis (the inner layer). Melanocytes are found in the epidermis and they contain melanin, which gives the skin its color. Melanoma is sometimes called cutaneous melanoma or malignant melanoma.
Melanoma is a more serious type of cancer than the more common skin cancers, basal cell cancer or squamous cell cancer, which begin in the basal or squamous cells of the epidermis. If you have basal cell or squamous cell cancer of the skin, refer to the patient information statement for skin cancer.
Like most cancers, melanoma is best treated when it is found (diagnosed) early. Melanoma can spread (metastasize) quickly to other parts of the body through the lymph system or through the blood. (Lymph nodes are small, bean-shaped structures that are found throughout the body; they produce and store infection-fighting cells.) You should see your doctor if you have any of the following warning signs of melanoma: change in the size, shape, or color of a mole; oozing or bleeding from a mole; or a mole that feels itchy, hard, lumpy, swollen, or tender to the touch. Melanoma can also appear on the body as a new mole. Men most often get melanoma on the trunk (the area of the body between the shoulders and hips) or on the head or neck; women most often get melanoma on the arms and legs.
If you have signs of skin cancer, your doctor will examine your skin carefully. If a mole or pigmented area doesn't look normal, your doctor will cut it out (called local excision) and look at it under the microscope to see if it contains cancer. This is usually done in a doctor's office. It is important that this biopsy is done correctly.
Are there precautions that will reduce my risk?
The following six steps have been recommended by the American Academy of Dermatology and the Skin Cancer Foundation to help reduce the risk of sunburn and skin cancer.
- Minimize your exposure to the sun at midday and between the hours of 10:00AM and 3:00PM.
- Apply sunscreen with at least a SPF-15 or higher, to all areas of the body which are exposed to the sun.
- Reapply sunscreen every two hours, even on cloudy days. Reapply after swimming or perspiring.
- Wear clothing that covers your body and shades your face. (Hats should provide shade for both the face and back of the neck.)
- Avoid exposure to UV radiation from sunlamps or tanning parlors.
- Protect your children. Keep them from excessive sun exposure when the sun is strongest (10:00AM and 3:00PM), and apply sunscreen liberally and frequently to children 6 months of age and older. Do not use sunscreen on children under 6 months of age. Parents with children under 6 months of age should severely limit their children's sun exposure
DIAGNOSIS AND TREATMENT
Skin cancer is diagnosed by removing all or part of the growth and examining its cells under a microscope. It can be treated by a number of methods, depending on the type of cancer, its stage of growth, and its location on your body.
Most skin cancers in the face are removed surgically, by a facial cosmetic surgeon or a dermatologist. If the cancer is small, the procedure can be done quickly and easily, in an outpatient facility or the physician's office, using local anesthesia. The procedure may be a simple excision, which usually leaves a thin, barely visible scar. Or curettage and desiccation may be performed. In this procedure the cancer is scraped out with an electric current to control bleeding and kill any remaining cancer cells. This leaves a slightly larger, white scar. In either case, the risks of the surgery are low.
If the cancer is large, however, or if it has spread to the lymph glands or elsewhere in the body, major surgery may be required. Other possible treat- ments for skin cancer include cryosurgery (freezing the cancer cells), radiation therapy (using x-rays), topical chemotherapy (anti-cancer drugs applied to the skin), and Mohs surgery, a special procedure in which the cancer is shaved off one layer at a time. (Mohs surgery is performed only by specially trained physicians and often requires a reconstructive procedure as follow-up.)
DISCUSSING YOUR OPTIONS AND CONCERNS
All of the treatments mentioned above, when chosen carefully and appropriately, have good cure rates for most basal cell and squamous cell cancers -and even for malignant melanoma, if it's caught very early, before it's had a chance to spread.
You should discuss these choices thoroughly with your doctor before beginning treatment. Find out which options are available to you...how effective they're likely to be for your particular cancer...the possible risks and side effects...who can best perform them...and the cosmetic and functional results you can expect. If you have any doubts about the outcome, get a second opinion from a plastic surgeon before you begin treatment.
A WORD ABOUT RECONSTRUCTION
The different techniques used in treating skin cancers can be life saving, but they may leave a patient with less than pleasing cosmetic or functional results. Depending on the location and severity of the cancer, the consequences may range from a small but unsightly scar to permanent changes in facial structures such as your nose, ear, or lip.
In such cases, no matter who performs the initial treatment, the facial cosmetic surgeon can be an important part of the treatment team. Reconstructive techniques- ranging from a simple scar revision to a complex transfer of tissue flaps from elsewhere on the body-can often repair damaged tissue, rebuild body parts, and restore most patients to acceptable appearance and function.