Overview
Melanoma, the most serious type of skin cancer, develops in the cells (melanocytes) that produce melanin — the pigment that gives your skin its color. Melanoma can also form in your eyes and, rarely, inside your body, such as in your nose or throat.
Knowing the warning signs of skin cancer can help ensure that cancerous changes are detected and treated before the cancer has spread. Melanoma can be treated successfully if it is detected early.
Symptoms
Melanomas can develop anywhere on your body and 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 fingernail beds. These hidden melanomas are more common in people with darker skin.
The first melanoma signs and symptoms often are:
- A change in an existing mole
- The development of a new pigmented or unusual-looking growth on your skin
Melanoma doesn’t always begin as a mole. It can also occur on otherwise normal-appearing skin.
Normal moles
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 (about 6 millimeters) in diameter — the size of a pencil eraser.
Most moles begin appearing in childhood and new moles may form until about age 40. By the time they are adults, most people have between 10 and 40 moles. Moles may change in appearance over time and some may even disappear with age.
Unusual moles that may indicate melanoma
To help you identify characteristics of unusual moles that may indicate melanomas or other skin cancers, think of the letters ABCDE:
- 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 — 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 1/4 inch (about 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.
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.
Hidden melanomas
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.
- Melanoma in the mouth, digestive tract, urinary tract, or vagina.
- Melanoma in the eye.
Causes
Melanoma occurs when something goes wrong 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 fall 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. Still, doctors believe exposure to ultraviolet (UV) radiation from the sun and from tanning lamps and beds is the leading cause of melanoma.
UV light doesn’t cause all melanomas, especially those that occur in places on your body that don’t receive exposure to sunlight. This indicates that other factors may contribute to your risk of melanoma.
Risk factors
Factors that may increase your risk of melanoma include:
- Fair skin.
- A history of sunburn.One or more severe, blistering sunburns can increase your risk of melanoma.
- Excessive ultraviolet (UV) light exposure.
- Living closer to the equator or at a higher elevation.
- Having many moles or unusual moles.Having more than 50 ordinary moles on your body indicates an increased risk of melanoma. Also, having an unusual type of mole increases the risk of melanoma.
- A family history of melanoma.
- Weakened immune system.
Prevention
You can reduce your risk of melanoma and other types of skin cancer if you:
- Avoid the sun during the middle of the day.
- Wear sunscreen year-round.
- Wear protective clothing and suglasses.
- Avoid tanning lamps and beds.
- Become familiar with your skin so that you’ll notice changes.
Make an appointment with me or your dermatologist if you notice any skin changes that seem unusual.
I thank the Mayo Clinic for their information on Melanoma. Here is a link to their website.
