Everyone has moles. Although most people think a mole is just a round, dark brown spot, moles come in many shapes and sizes. Moles can be present at birth or acquired throughout life, but most appear during the first 20 years of a person's life. The incidence of moles, or nevi, as doctors call them, tend to increase in number throughout childhood, peak in adolescence, and typically wane in older adulthood. Most moles are not cancerous and don't cause a problem. But occasionally, a mole changes in appearance, is irritating or may appear "unattractive." In these cases, the mole or moles may need to be removed.

ABCD's to watch for:

Asymmetry
One side of a mole doesn't look like the other side

Border
The edges of a mole are ragged or uneven.

Color
More than one color is present in a single mole. Melanoma may include streaks of tan, brown, black, red, white, and blue.

Diameter
A mole becomes larger than pencil eraser size or changes its shape.