• Mayo Clinic Q and A: Don’t let a bleeding mole go unchecked

a medical illustration of a woman doing a skin self-examinationDEAR MAYO CLINIC: Should I see a health care provider for a mole that bleeds occasionally?

ANSWER: Yes. Although it may not be serious, a mole that bleeds is a possible sign of melanoma — a rare but serious skin cancer that can spread if left untreated. Being evaluated by a dermatologist once a year and checking your skin regularly are two excellent steps you can take to catch melanoma and other types of skin cancer early. The sooner skin cancer is found, the better the chances are of curing it.

Moles are groups of pigment cells, and nearly everyone has them. Most are harmless, but it’s possible for melanoma to develop in or near a mole. A change in a mole — or a new mole — can be a first sign of melanoma. Melanoma develops in cells called melanocytes that produce melanin — the pigment that gives your skin its color. The exact cause of all melanomas isn’t clear, but exposure to ultraviolet, or UV, radiation from sunlight or tanning lamps and beds increases your risk of developing the disease.

It’s not always easy to distinguish melanoma from a normal mole or other area of pigmentation. One of the most important things you can do is to become familiar with the location and pattern of your moles, and monitor for changes. Examine your body in front of a mirror. Ask someone to look at your back. If you notice any changes in shape, size or color of a mole, or new mole growth, show it to your health care provider. If it looks suspicious, your health care provider or a dermatologist can remove the mole (biopsy) to have it checked for cancerous cells. This procedure is usually quick, and it may be all the treatment you need.

When checking your moles, follow the ABCDE guide from the American Academy of Dermatology. Look for:

  • Asymmetry (one half of a mole looks different than the other half)
  • Border irregularity (borders of a mole are uneven, jagged or scalloped)
  • Color variations within the same mole
  • Diameter greater than the eraser tip of a pencil
  • Evolving color, shape or size

an image of the ABCDE criteria used to identify characteristics of unusual moles that may indicate melanomas or other skin cancers

Moles that are larger than about a quarter of an inch across — or about the size of a pencil eraser — should be evaluated by a health care provider. Also talk to your health care provider about any itching, tenderness or pain, as well as changes in skin texture, such as scaling, shedding of skin or oozing. In addition to melanoma, other kinds of skin cancer, including basal cell carcinoma and squamous cell carcinoma, tend to look like pink, red or scaly spots on your skin that do not go away on their own.

Finally, remember that prevention is key. Protect your skin as much as you can. Whenever possible, stay out of the sun during the middle of the day when UV light is the strongest. When you are outdoors, use plenty of sunscreen — with a sun protection factor, or SPF, of at least 45 — in all seasons, and put it on your skin often. (adapted from Mayo Clinic Health Letter) — Dr. Jason Sluzevich, Dermatology, Mayo Clinic, Jacksonville, Florida

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