Is this mole dangerous?

Most moles are harmless, but some can develop into melanoma—the most serious type of skin cancer. Knowing what to look for can help you catch changes early, when treatment is most effective.

Dermatologists use a simple visual guide to help patients understand what’s normal and what might need a closer look.

The ABCDE Guide to Concerning Moles

The ABCDE rule helps identify features that may suggest melanoma.

A — Asymmetry

If one half of the mole doesn’t match the other half, that’s a sign the mole may be growing unevenly.

B — Border

Worrisome moles often have irregular, scalloped, or blurry edges.

C — Color

A mole with multiple colors—brown, black, red, blue, or white—or uneven shading is more concerning than a single, uniform color.

D — Diameter

Moles larger than 6 mm (about the size of a pencil eraser) raise suspicion, though melanoma can be smaller.

E — Evolving

This is the most important sign. Any mole that changes in size, shape, color, or texture should be checked by a dermatologist.

Other Warning Signs to Know

Beyond ABCDE, there are additional symptoms worth noting:

The “Ugly Duckling” Sign

If one mole looks different from all your others, it deserves extra attention.

New Moles in Adulthood

Moles that appear after age 30 should be monitored more closely.

Itching, Bleeding, or Pain

These symptoms can signal irritation—or something more serious.

A Growing Pink or Skin-Colored Bump

Some melanomas are not dark; they can appear pale, pink, or almost translucent.

What Causes Melanoma?

Major risk factors include:

• UV exposure (sunburns, tanning beds)

• Fair skin or easily sunburned skin

• Family history of melanoma

• Personal history of skin cancer

• Having many moles or atypical moles

Sun protection—daily SPF 30+, protective clothing, and avoiding peak UV hours—is key to prevention.

What to Expect at a Total Body Skin Exam

A dermatologist will perform a full-body skin exam using a dermatoscope (a special magnifying tool). If a mole looks suspicious, a small biopsy may be done—usually a quick, well-tolerated procedure.

Most biopsies do not come back as melanoma, but checking is always better than waiting.

Conclusions

You don’t need to memorize every detail of the ABCDEs, but you should know your skin. If something looks new, different, or concerning, trust your instincts and get it evaluated. Early detection saves lives—simple as that.