An example of how melanoma tumors are often asymmetrical (lopsided), unlike non-cancerous moles.
If you have 50 or more normal moles (or 5 or more "dysplastic" moles), you should check your skin thoroughly several times per year. (Even if you don't have any moles, you should do a skin self-exam once per year.) If you see any of the following signs, contact your doctor:
- A new, possibly large, irregularly shaped, dark brownish spot with darker or black areas.
- A simple mole that changes in color (particularly turning darker), size (growing), or texture (becoming firmer), and/or flakes or bleeds.
- A suspicious change in an existing mole or spot.
- A lesion with an irregular border and red, white, blue, gray, or bluish-black areas or spots.
- Dark lesions under the fingernails or toenails, on the palms, soles, tips of fingers and toes, or on mucous membranes (the skin that lines the mouth, nose, vagina, and anus).