Last month,United States Senator John McCain was treated for the most serious kind of skin cancer,malignant melanoma.
Doctors removed the cancer in an operation.
Later tests showed that the cancer had not spread from the skin to other organs.
Malignant melanoma can be cured if it is removed before it spreads to other parts of the body.
But the disease can kill if it spreads.
The World Health Organization says two-hundred-thousand people around the world are found to have malignant melanoma each year.
About forty-seven-thousand new cases of melanoma are found in the United States each year.
The American Dermatology Association says almost eight-thousand Americans will die this year from the disease.
The cancer begins in body cells that produce a brown color.
It usually first grows in a dark area of skin called a mole.
Melanoma most often is recognized as a dark area with an unusual shape.
An operation to remove the cancerous cells can cure melanoma if the cancer has not spread.
Doctors treat melanoma that has spread with chemotherapy drugs to kill any cancer cells that were not removed in the operation.
Radiation also may be used to kill cancerous cells and reduce the size of any cancerous growths.
The newest kind of treatment for melanoma is the use of molecules produced by the human body.
The purpose of this treatment is to improve the body's own defenses against cancer cells.
The five-year survival rate for melanoma that has spread to the lymph nodes is thirty to forty percent.
The five-year survival rate is only twelve percent if the cancer has spread to other organs such as the liver,bones or brain.
Doctors believe too much sunlight can cause melanoma.
This is especially true for people who have light skin and were burned by the sun when they were young.
Some people are more likely than others to develop melanoma.
These include people whose family members had the disease.
They also include people who have a large number of moles on their bodies.
Doctors say people should protect their skin from the sun.
They should always wear a hat and protective clothing.
They should use a sun protection liquid.
Doctors also say people should examine their bodies often for any changes in moles or the presence of new dark areas.
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