What is Melanoma (Skin Cancer)?
Melanoma, the most serious type of skin cancer, develops in the cells that produce melanin — the pigment that gives your skin its color. Melanoma can also form in other organs.
The exact cause of all melanomas isn’t clear, (See the National Cancer Institute Informational online booklet) but exposure to ultraviolet (UV) radiation from sunlight or tanning lamps and beds increases your risk of developing melanoma. Other factors, such as your genetic makeup, likely also play a role.
Limiting your sun exposure and avoiding tanning lamps and beds can help reduce your risk of melanoma. Making sure you know the warning signs of skin cancer can help ensure that cancerous changes are detected and treated before the cancer has a chance to spread. Melanoma can be treated successfully if it is detected early.
What are the symptoms of melanoma?
Melanomas can develop anywhere on your body, but they most often develop in areas that have had exposure to the sun, such as your back, legs, arms and face. Melanomas can also occur in areas that don’t receive much sun exposure, such as the soles of your feet, palms of your hands and on fingernail beds. These hidden melanomas are more common in people with darker skin.
What do normal moles look like?
Normal moles are generally a uniform color, such as tan, brown or black, with a distinct border separating the mole from your surrounding skin. They’re oval or round and usually smaller than 1/4 inch (6 millimeters) in diameter — the size of a pencil eraser.
Most people have between 10 and 40 moles. Many of these develop by age 40, although moles may change in appearance over time — some may even disappear with age.
How do you use the A-B-C-D-E guide?
Characteristics of unusual moles that may indicate melanomas or other skin cancers follow the A-B-C-D-E guide developed by the American Academy of Dermatology:
A is for asymmetrical shape. Look for moles with irregular shapes, such as two very different-looking halves
B is for irregular border. Look for moles with irregular, notched or scalloped borders, these may be characteristics of melanomas
C is for changes in color. Look for growths that have many colors or an uneven distribution of color
D is for diameter. Look for new growth in a mole larger than about 1/4 inch (6 millimeters)
E is for evolving. Look for changes over time, such as a mole that grows in size or that changes color or shape. Moles may also evolve to develop new signs and symptoms, such as new itchiness or bleeding
Other suspicious changes in a mole may include: scaly skin, itching, spreading of pigment from the mole into the surrounding skin, oozing or bleeding. Cancerous (malignant) moles vary greatly in appearance. Some may show all of the changes listed above, while others may have only one or two unusual characteristics.
What is a hidden melanoma?
Melanomas can also develop in areas of your body that have little or no exposure to the sun, such as the spaces between your toes and on your palms, soles, scalp or genitals. These are sometimes referred to as hidden melanomas; because they occur in places most people wouldn’t think to check. When melanoma occurs in people with darker skin, it’s more likely to occur in a hidden area.
Hidden melanomas include
Melanoma under a nail: Subungual melanoma is a rare form that occurs under a nail and can affect the hands or the feet. It’s more common in blacks and in other people with darker skin pigment. The first indication of a subungual melanoma is usually a brown or black discoloration that’s often mistaken for a bruise (hematoma) of the nail.
Melanoma in the mouth, digestive tract, urinary tract or vagina: Mucosal melanoma develops in the mucous membrane that lines the nose, mouth, esophagus, anus, urinary tract and vagina. Mucosal melanomas are especially difficult to detect because they can easily be mistaken for other, far more common conditions. A melanoma in a woman’s vagina can cause itching and bleeding. Anal melanoma can cause anal bleeding and pain during bowel movements. Melanoma that occurs in the esophagus can cause difficulty swallowing.
Melanoma in the eye: Eye melanoma, also called ocular melanoma, occurs in the uvea — the layer beneath the white of the eye (sclera). An eye melanoma may cause vision changes and may be diagnosed during an eye exam.
What causes melanoma?
Melanoma occurs when something goes awry in the melanin-producing cells (melanocytes) that give color to your skin. Normally, skin cells develop in a controlled and orderly way — healthy new cells push older cells toward your skin’s surface, where they die and eventually are sloughed off. But when some cells develop DNA damage, new cells may begin to grow out of control and can eventually form a mass of cancerous cells.
Just what damages DNA in skin cells and how this leads to melanoma isn’t clear. It’s likely that a combination of factors, including environmental and genetic factors, causes melanoma.
What are the risk factors of melanoma?
Fair skin: Having less pigment (melanin) in your skin means you have less protection from damaging UV radiation. If you have blond or red hair, light-colored eyes, and you freckle or sunburn easily, you’re more likely to develop melanoma than someone with a darker complexion. Melanoma can develop in people with darker complexions, including Hispanics and blacks.
A history of sunburn: One or more severe, blistering sunburns as a child or teenager can increase your risk of melanoma as an adult.
Excessive ultraviolet (UV) light exposure: Exposure to UV radiation, which comes from the sun and from tanning beds, can increase the risk of skin cancer, including melanoma.
Living closer to the equator or at a higher elevation: People living closer to the earth’s equator, where the sun’s rays are more direct, experience higher amounts of UV radiation, as compared with those living in higher latitudes. In addition, if you live at a high elevation you’re exposed to more UV radiation.
Having many moles or unusual moles: Having more than 50 dysplastic nevi on your body indicates an increased risk of melanoma. A dysplastic nevus is an unusual type of mole that tends to be larger (greater than 1/5 inch or 5 millimeters) than a normal mole and have irregular borders and a mixture of colors.
A family history of melanoma: If a close relative, such as a parent, child or sibling, has had melanoma, you have a greater chance of developing it too.
Weakened immune system: People with weakened immune systems have an increased risk of skin cancer. This includes people who have HIV/AIDS and those who have undergone organ transplants.
How is melanoma screened and diagnosed?
Ask your provider whether you should consider periodic screening for skin cancer. You and your provider may consider screening options such as:
Skin exams by a trained professional: The American Cancer Society (ACS) recommends periodic skin exams as part of your usual checkups with your doctor. During a skin exam, your provider will conduct a head-to-toe inspection of your skin.
Skin exams you do at home: In addition, the ACS and the American Academy of Dermatology recommend occasional self-exams. A self-exam may help you learn the moles, freckles and other skin marks that are normal for you, so you can notice any changes. It’s best to do this standing in front of a full-length mirror while using a hand-held mirror to inspect hard-to-see areas. Be sure to check the fronts, backs and sides of your arms and legs. In addition, check your groin, scalp, fingernails, your soles and the spaces between your toes.
Diagnosing melanoma: Sometimes cancer can be detected simply by looking at your skin, but the only way to accurately diagnose melanoma is with a biopsy. In this procedure, all or part of the suspicious mole or growth is removed, and a pathologist analyzes the sample.
Melanoma stages: If you receive a diagnosis of melanoma, the next step is to determine the extent, or stage, of the cancer. To assign a stage to your melanoma, your provider will:
Determine the thickness: The thickness of a melanoma is determined by carefully examining the melanoma under a microscope. The thickness of a melanoma helps your provider decide on a treatment plan. In general, the thicker the tumor, the more serious the disease.
See if the melanoma has spread: To determine whether your melanoma has spread to nearby lymph nodes, the surgeon that your provider refers you to may use a procedure known as a sentinel node biopsy. During a sentinel node biopsy, a dye is injected in the area where your melanoma was removed. The dye flows to the nearby lymph nodes. The first lymph nodes to take up the dye are removed and tested for cancer cells. If these first lymph nodes (sentinel lymph nodes) are cancer-free, there’s a good chance that the melanoma has not spread beyond the area where it was first discovered.
How is melanoma treated?
The best treatment for you depends on your stage of cancer and your age, overall health and personal preferences. Melanoma is staged using the Roman numerals I through IV. A stage I melanoma is small and has a very successful treatment rate. The higher the numeral, the lower the chances of a full recovery. By stage IV, the cancer has spread beyond your skin to other organs, such as your lungs or liver.
Treating early-stage melanomas
Treatment for early-stage melanomas usually includes surgery to remove the melanoma. A very thin melanoma may have been entirely removed during the biopsy and require no further treatment. Otherwise, your surgeon will remove the cancer as well as a small border of normal skin and a layer of tissue beneath the skin. In the early-stage melanomas, this may be the only treatment needed.
Treating melanomas that have spread beyond the skin
If melanoma has spread beyond the skin, treatment options may include:
Surgery to remove affected lymph nodes: If melanoma has spread to nearby lymph nodes, your surgeon may remove the affected nodes. Additional treatments before or after surgery may also be recommended.
Chemotherapy: Chemotherapy uses drugs to destroy cancer cells. Chemotherapy can be administered intravenously, in pill form or both, so that it travels throughout your body.
Radiation therapy: This treatment uses high-powered energy beams, such as X-rays, to kill cancer cells. It’s sometimes used to help relieve symptoms of melanoma that has spread to another organ.
Biological therapy (immunotherapy): Biological therapy boosts your immune system to help your body fight cancer. These treatments are made of substances produced by the body or similar substances produced in a laboratory.
Can you prevent melanoma?
Although there is not one thing that will prevent melanoma, here are a few things that can help:
Avoid midday sun: Avoid the sun when its rays are the strongest. For most places, this is between about 10 a.m. and 4 p.m. Because the sun’s rays are strongest during this period, try to schedule outdoor activities for other times of the day, even in winter or when the sky is cloudy. You absorb UV radiation year-round, and clouds offer little protection from damaging rays.
Wear sunscreen year-round: Choose a broad-spectrum sunscreen that has a sun protection factor (SPF) of at least 30. Use a generous amount of sunscreen on all exposed skin, including your lips, the tips of your ears, and the backs of your hands and neck. Apply sunscreen 20 to 30 minutes before sun exposure and reapply it frequently while you’re exposed to the sun. Be sure to reapply it after swimming or exercising.
Wear protective clothing: Sunscreens don’t provide complete protection from UV rays, so wear tightly woven clothing that covers your arms and legs, and a broad-brimmed hat, which provides more protection than a baseball cap or visor does. Some companies also sell photo protective clothing. Your dermatologist can recommend an appropriate brand. Don’t forget sunglasses. Look for those that block both types of UV radiation — UVA and UVB rays.
Avoid tanning beds: Tanning beds emit UV radiation, which can increase the risk of skin cancer.
Become familiar with your skin, so you’ll notice changes: Examine your skin so that you become familiar with what your skin normally looks like. This way, you may be more likely to notice any skin changes. With the help of mirrors, check your face, neck, ears and scalp. Examine your chest and trunk, and the tops and undersides of your arms and hands. Examine both the front and back of your legs, and your feet, including the soles and the spaces between your toes. Also check your genital area, and between your buttocks. If you notice anything unusual, point it out to your provider at your next appointment.