What Is Melanoma?
More skin cancers are diagnosed each year than cancers of the prostate, breast, lung, colon, uterus, ovaries, and pancreas combined. Melanoma accounts for less than 5% of all skin cancer cases.
However it is the most serious form of skin cancer and accounts for most skin cancer deaths. If it is recognized and treated early, melanoma is nearly 100 percent curable. But if it is not, the cancer can advance and spread to other parts of the body, where it becomes hard to treat and can be fatal. Overall, the lifetime risk of getting melanoma is about 1 in 50 for whites, 1 in 1,000 for African Americans, and 1 in 200 for Hispanics. The American Cancer Society estimated that in 2008 there were about 62,480 new cases of melanoma in the United States. Approximately 8,420 people in the United States died from melanoma in 2008.
Melanoma is a malignant tumor that originates in melanocytes, the cells which produce the pigment melanin that colors our skin, hair, and eyes. For this reason the majority of melanomas are black or brown; however, some melanomas are skin-colored, pink, red, purple, blue or white.
What Causes Melanoma?
We do not yet know exactly what causes melanoma skin cancer. But we do know that certain risk factors are linked to this disease:
- UV (ultraviolet) light: Too much exposure to UV radiation is thought to be the biggest risk factor for most melanomas. The main source of UV is sunlight. Tanning lamps and booths are also sources of UV light.
- Moles: A mole is a benign skin tumor. Certain types of moles increase a person’s chance of getting melanoma. The chance of any single mole turning into cancer is very low. But a person who has many moles is more likely to develop melanoma. These people should have very thorough skin exams by a dermatologist.
- Fair skin: People with fair skin, freckles, or red or blonde hair have a higher risk of melanoma.
- A family history of melanoma: Approximately 10% of people with melanoma have a close relative with the disease
- A past history of melanoma
- Weakened immune systems
- Xeroderma pigmentosum (XP)
Having a risk factor, or even several risk factors, does not mean that you will get the disease. And many people who get the disease may not have any known risk factors. Even if a person with melanoma has a risk factor, it is often very hard to know how much that risk factor may have contributed to the cancer.
Not all melanomas can be prevented, but there are ways to reduce your risk.
- Limit UV exposure.
- Protect your skin with clothing: Clothes vary in how much they can protect you. Long-sleeved shirts, long pants, or long skirts are the most protective. Dark colors are better than light colors. A tightly woven
fabric protects better than loosely woven clothing. And dry clothing is better than wet clothing. Some clothing is made with built-in UV protection.
- Wear a hat: A hat with at least a 2- to 3-inch brim all around is good because it protects the neck, ears, eyes, forehead, nose, and scalp.
- Use sunscreen and lip balm with an SPF of 15 or higher.
- Wear sunglasses.
- Protect children: Be especially careful about sun protection for children. Children tend to spend more time outdoors and they burn more easily.
- Avoid other sources of UV light such as tanning beds and sun lamps.
- Check for abnormal moles and have them removed.
For more information on how to protect yourself and your family, see the American Cancer Society Document, Skin Cancer Prevention and Early Detection.
Self Exams: What To Look For
Melanoma can often be found early. Everyone can do things to help find this cancer early, when it is curable.
It’s important to check your own skin about once a month. You should know the pattern of moles, freckles, and other marks on your skin so that you’ll notice any changes. Spots on the skin that change in size, shape, or color should be seen by a doctor right away. It’s important to know the difference between melanoma and a harmless mole. A normal mole is most often an evenly colored brown, tan, or black spot on the skin. It can be either flat or raised. It can be round or oval. Moles are usually less than 1/4 inch across, or about the width of a pencil eraser. Moles can be present at birth or they can appear later. Once a mole has developed, it will most often stay the same size, shape, and color for many years. Most people have moles, and almost all moles are harmless. But it is important to notice changes in a mole (such as its size, shape, or color) that suggest a melanoma may be starting.
The ABCDE rule can help you tell a normal mole from an abnormal mole. Moles that have any of these signs should be checked by your doctor. ABCDE stands for the following:
A symmetry: One half of the mole does not match the other half.
B order irregularity: The edges of the mole are irregular or not smooth. They may look ragged, blurred, or notched.
C olor: The color over the mole is not the same all over. There may be shades of tan, brown, or black, and sometimes patches of pink, red, blue, or white.
D iameter: The mole is larger than about ¼ inch– about the size of a pencil eraser– although sometimes melanomas can be smaller.
E volution-Ordinary moles usually do not change over time. A mole that suddenly grows in size or rapidly becomes elevated is suspicious for melanoma.
Still, some melanomas do not fit the “rules” above. It may be hard to tell if the mole is normal or not, so you should show your doctor anything that you are unsure of.
1 The American Cancer Society