Unusual moles may be an indicator or marker for the development of melanoma. Look for A: asymmetrical. Any mole with irregular shape. B: any mole with an irregular border with notches or scallops. C: changes in color, particularly if they are uneven with increase or even loss of color. D: diameter. We are most concerned with growth larger than six millimeters, or just larger than a pencil eraser. E: evolving. Any mole that changes over time grows in size, shape, or color. Of course, itching, burning or bleeding are immediate signs that require evaluation.