The ABCD Rule and Melanoma Danger Signs

Finding melanoma early is the key to curing this vicious cancer. Learn the ABCD mnemonic for recognizing moles and growths that might be cancerous. Though most (if not all) of your "suspicious" moles will turn out to be normal non-cancerous moles, it is much better to be safe than to not see, or ignore, an early melanoma. Be sure to review how to do a monthly skin examination to properly look for abnormal growths.

If your mole or growth has one or more of the ABCDEs, you should show it to your physician as soon as possible!

Asymmetry can be assessed by comparing one half of the growth to the other half to determine if the halves are equal in size. Unequal or asymmetric moles are suspicious.

Symmetric - Normal


If the mole's border is irregular, notched, scalloped, or indistinct, it is more likely to be cancerous (or precancerous) and is thus suspicious.

Regular Border - Normal

Irregular Border

Variation of color (e.g., more than one color or shade) within a mole is a suspicious finding. Different shades of browns, blues, reds, whites, and blacks are all concerning.

One Color - Normal

Color Variance

Any mole that has a diameter larger than a pencil's eraser in size (> 6 mm) should be considered suspicious.

If a mole is elevated, or raised from the skin, it should be considered suspicious.

Other Danger Signs of Malignant Melanoma
• Change in color, especially multiple shades of dark brown or black; red, white and blue,
• Change or spreading of color from the edge of the mole into surrounding skin.
• Change in size, especially sudden or continuous enlargement.
• Change in shape, especially development of irregular margins or border.
• Change in elevation, especially sudden elevation of a previously flat mole.
• Change in the surface texture of a mole, especially scaliness, erosion, oozing, crusting, ulceration, or bleeding.
• Change in the the surrounding skin, especially redness, swelling, or new moles.
• Change in sensation, especially itching, tenderness, or pain.

Basically, any mole or growth that is CHANGING needs to be checked by a doctor