What is skin cancer?
Skin cancer is a malignant tumor that grows in the skin cells. In the US alone, more than 1 million Americans will be diagnosed in 2009 with nonmelanoma skin cancer, and 68,720 will be diagnosed with melanoma, according to the American Cancer Society.
What are the different types of skin cancer?
There are three main types of skin cancer, including:
Basal cell carcinoma accounts for approximately 80 percent of all skin cancers. This highly treatable cancer starts in the basal cell layer of the epidermis (the top layer of skin) and grows very slowly. Basal cell carcinoma usually appears as a small, shiny bump or nodule on the skin - mainly those areas exposed to the sun, such as the head, neck, arms, hands, and face. It commonly occurs among persons with light-colored eyes, hair, and complexion.
Squamous cell carcinoma, although more aggressive than basal cell carcinoma, is highly treatable. It accounts for about 20 percent of all skin cancers. Squamous cell carcinoma may appear as nodules or red, scaly patches of skin, and may be found on the face, ears, lips, and mouth. However, squamous cell carcinoma can spread to other parts of the body. This type of skin cancer is usually found in fair-skinned people.
Malignant melanoma accounts for a small percentage of all skin cancers, but accounts for most deaths from skin cancer. Malignant melanoma starts in the melanocytes - cells that produce pigment in the skin. Malignant melanomas usually begin as a mole that then turns cancerous. This cancer may spread quickly. Malignant melanoma most often appears on fair-skinned men and women, but persons with all skin types may be affected.
Distinguishing benign moles from melanoma:
To prevent melanoma, it is important to examine your skin on a regular basis, and become familiar with moles, and other skin conditions, in order to better identify changes. According to recent research, certain moles are at higher risk for changing into malignant melanoma. Moles that are present at birth, and atypical moles, have a greater chance of becoming malignant. Recognizing changes in moles is crucial in detecting malignant melanoma at its earliest stage. The ABCD warning signs are:
- Asymmetry when half of the mole does not match the other half
- Border when the border (edges) of the mole are ragged or irregular
- Color when the color of the mole varies throughout
- Diameter if the mole's diameter is larger than a pencil's eraser
Melanomas vary greatly in appearance. Some melanomas may show all of the ABCD characteristics, while other may only show changes in one or two characteristics. Always consult your physician for a diagnosis.
What are the risk factors for melanoma?
Skin cancer is more common in fair-skinned people - especially those with blond or red hair, who have light-colored eyes. Skin cancer is rare in children. However, no one is safe from skin cancer. Other risk factors include:
- family history of melanoma
- sun exposure: The amount of time spent unprotected in the sun directly affects your risk of skin cancer.
- early childhood sunburns: Research has shown that sunburns early in life increase a person's risk for skin cancer later in life.
- many freckles
- many ordinary moles (more than 50)
- dysplastic nevi
Prevention of skin cancer:
The American Academy of Dermatology (AAD) has declared war on skin cancer by recommending these three preventive steps:
- Wear protective clothing, including a hat with a four-inch brim and sunglasses.
- Apply sunscreen all over your body and avoid the midday sun from 10 a.m. to 4 p.m.
- Regularly use a broad-spectrum sunscreen with an SPF of 15 or higher, even on cloudy days.
- The following steps have been recommended by the AAD and the Skin Cancer Foundation to help reduce the risk of sunburn and skin cancer.
- Minimize exposure to the sun at midday—between the hours of 10 a.m. and 4 p.m.
- Apply sunscreen, with at least a SPF-15 or higher that protects against both UVA and UVB rays, to all areas of the body that are exposed to the sun.
- Reapply sunscreen every two hours, even on cloudy days. Reapply after swimming or perspiring.
- Use extra caution near water, snow, and sand—they reflect the damaging rays of the sun, which can increase the chance of sunburn.
- Wear clothing that covers the body and shades the face. Hats should provide shade for both the face and back of the neck. Wearing sunglasses will reduce the amount of rays reaching the eye by filtering as much as 80 percent of the rays, and protecting the lids of our eyes as well as the lens.
- Avoid exposure to UV radiation from sunlamps or tanning parlors.
- Protect children. Keep them from excessive sun exposure when the sun is strongest (between 10 a.m. and 3 p.m.) by having them play in the shade, wear protective clothing, and use sunscreen liberally and frequently—for children 6 months of age and older.
Get vitamin D safely through a healthy diet that may include vitamin supplements. Don't seek the sun.
Remember, sand and pavement reflect UV rays even under the umbrella. Snow is even a particularly good reflector of UV rays. Reflective surfaces can reflect up to 85 percent of the damaging sun rays.
How to perform a skin self-examination:
Finding suspicious moles or skin cancer early is the key to treating skin cancer successfully. A skin self-exam is usually the first step in detecting skin cancer. The following suggested method of self-examination comes from the American Cancer Society: Examine your body front and back in mirror, then the right and left sides, with your arms raised. Bend your elbows, look carefully at your forearms, the back of your upper arms, and the palms of your hands. Check between your fingers and look at your nail beds. Look at backs of your legs and feet, spaces between your toes, your toenail beds, and the soles of your feet. Examine the back of your neck and scalp with a hand mirror. Check your back, buttocks, and genital area with a hand mirror. Become familiar with your skin and the pattern of your moles, freckles, and other marks. Be alert to changes in the number, size, shape, and color of pigmented areas. Follow the ABCD when examining moles of other pigmented areas and consult your physician promptly if you notice any changes.
Treatments for skin cancer:
Specific treatment for skin cancer will be determined by your physician based on:
- your age, overall health, and medical history
- extent and type of the disease
- your tolerance for specific medications, procedures, or therapies
- expectations for the course of the disease
- your opinion or preference
There are several kinds of treatments for skin cancer, including the following:
Surgery is a common treatment for skin cancer. It is used in most treated cases. Some types of skin cancer growths can be removed very easily and require only very minor surgery, while others may require a more extensive surgical procedure. Surgery may include the following procedures:
Using liquid nitrogen, cryosurgery uses an instrument that sprays the liquid onto the skin, freezing and destroying the tissue.
- Curettage and electrodesiccation
This common type of surgery involves scraping away skin tissue with a curette (a sharp surgical instrument), followed by cauterizing the wound with an electrosurgical unit.
A scalpel (sharp surgical instrument) may be used to excise and remove the growth. The wound is usually stitched or held closed with skin clips.
Mohs' microscopically controlled surgery
This type of surgery involves excising a lesion, layer by layer. Each piece of excised tissue is examined under a microscope. Tissue is progressively excised until no tumor cells are seen. The goal of this type of surgery is to remove all of the malignant cells and as little normal tissue as possible. It is often used with recurring tumors.
Laser surgery uses a narrow beam of light to remove cancer cells, and is often used with tumors located on the outer layer of skin.
X-rays are used to kill cancer cells and shrink tumors.
Other types of treatment include the following:
Topical chemotherapy—chemotherapy given as a cream or lotion placed on the skin to kill cancer cells. Systemic chemotherapy—chemotherapy administered orally or intravenously (IV). Immunotherapy of melanoma is a complex type of treatment involving various approaches to boost the body's own immune system, helping it to slow the growth of the cancer.