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, in internal organs, such as your intestines.
The exact cause of all melanomas isn't clear, but exposure to ultraviolet (UV) radiation from sunlight or tanning lamps and beds increases your risk of developing melanoma. Limiting your exposure to UV radiation can help reduce your risk of melanoma.
The risk of melanoma seems to be increasing in people under 40, especially women. 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.
Melanoma is a form of skin cancer that begins in the cells (melanocytes) that produce the pigment in your skin. This illustration shows melanoma cells extending from the surface of the skin into the ...
Melanomas can develop anywhere on your body. 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 fingernail beds. These hidden melanomas are more common in people with darker skin.
The first melanoma signs and symptoms often are:
Melanoma doesn't always begin as a mole. It can also occur on otherwise normal-appearing skin.
Most people have between 10 and 45 moles. Many of these develop by age 40, although moles may change in appearance over time — some may even disappear with age.
Unusual moles that may indicate melanoma
Other suspicious changes in a mole may include:
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 include:
When to see a doctor
Moles are usually harmless. They may contain hairs or become raised or wrinkled. Talk to your doctor about any change in the color or size of a mole or if itching, pain, bleeding or inflammation ...
The first sign of melanoma is often a mole that changes size, shape or color. This melanoma shows color variations and an irregular border, both of which are melanoma warning signs. ...
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 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.
Where skin cancer develops
Skin cancer begins in the cells that make up the outer layer (epidermis) of your skin. One type of skin cancer called basal cell carcinoma begins in the basal cells, which make skin cells that ...
Factors that may increase your risk of melanoma include:
Preparing for your appointment
Start by seeing your family doctor or a general practitioner if you notice any skin changes that concern you. Depending on your situation and the outcome of any tests, you may be referred to a doctor who specializes in skin diseases (dermatologist) or to a doctor who specializes in cancer treatment (oncologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you get ready and know what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions can help you make the most of your time together. List your questions from most important to least important, in case time runs out. For melanoma, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask any other questions during your appointment.
Tests and diagnosis
Skin cancer screening
Some groups recommend periodic skin exams by your doctor and on your own. Other groups don't recommend skin cancer screening exams because it's not clear whether screening saves lives. Instead, finding an unusual mole could lead to a biopsy, which, if the mole is found to not be cancerous, could lead to unnecessary pain, anxiety and cost. Talk to your doctor about what screening is right for you based on your risk of skin cancer.
The type of skin biopsy procedure you undergo will depend on your situation.
Other factors may go into determining the aggressiveness of a melanoma, including whether the skin over the area has formed an open sore and how many dividing cancer cells are found when looking under a microscope.
Melanoma is staged using the Roman numerals I through IV. A stage I melanoma is small and has a very successful treatment rate. But 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.
During an excisional biopsy, the doctor removes an entire lump or an entire area of abnormal skin, including a portion of normal skin. You'll likely receive stitches to close the biopsy site after ...
During a punch biopsy, a doctor uses a special circular blade to remove deeper layers of skin for testing. Depending on the size, stitches may be necessary to close the wound. ...
Treatments and drugs
The best treatment for you depends on your stage of cancer and your age, overall health and personal preferences.
Treating early-stage melanomas
Treating melanomas that have spread beyond the skin
Experimental melanoma treatments
Some melanoma treatments being studied in clinical trials include:
The best news about melanoma is that many cases of skin cancer can be prevented by following these precautions:
Last Updated: 2012-06-12
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