Definition of melanoma: A form of skin cancer that begins in melanocytes (the cells that make the pigment melanin). Melanoma usually begins in a mole.
Estimated new cases and deaths from melanoma in the United States in 2007:
|  | New cases: 59,940
| | | Deaths: 8,110 |
Melanoma is the most serious type of cancer of the skin. Each year in the United States, more than 53,600 people learn they have melanoma. In some parts of the world, especially among Western countries, melanoma is becoming more common every year. In the United States, for example, the percentage of people who develop melanoma has more than doubled in the past 30 years. |