What to Look For The ABCD's of Melanoma Most people have a number of brownish spots on their skin - freckles, birthmarks, moles. Almost all such spots are normal, but some may be skin cancers. Key warning signs of melanoma are shown below. Be alert to irregularities in shape, edges, color, and size. Asymmetry, Border irregularity, Color variability, and Diameter larger than a pencil eraser.
Common moles are round and symmetrical.
The borders of early melanomas are often uneven and may have scalloped or notched edges. Common moles have smoother, more even borders. Color Common moles usually are a single shade of brown. Varied shades of brown, tan, or black are often the first sign of melanoma. As melanomas progress, the colors red, white and blue may appear.