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What Does Melanoma Look Like?

How to spot it, and what to know so you can get the help you need to stop it.

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The ABCDEs of Melanoma

These characteristics are used by dermatologists to classify melanomas of the skin. Look for these signs: Asymmetry, irregular Borders, more than one or uneven distribution of Color, or a large (greater than 6mm) Diameter. Finally, pay attention to the Evolution of your moles – know what’s normal for your skin and check it regularly for changes.1-2

Want this information as a handout? We’re proud to offer the ABCDEs in multiple languages:

If you see one or more of these, make an appointment with a dermatologist immediately.

A – Asymmetrical Shape

Melanoma lesions are often irregular, or not symmetrical, in shape. Benign moles are usually symmetrical.

B – Border

Typically, non-cancerous moles have smooth, even borders. Melanoma lesions usually have irregular borders that are difficult to define.

C – Color

The presence of more than one color (blue, black, brown, tan, etc.) or the uneven distribution of color can sometimes be a warning sign of melanoma. Benign moles are usually a single shade of brown or tan.

D – Diameter

Melanoma lesions are often greater than 6 millimeters in diameter (approximately the size of a pencil eraser).

E – Evolution (or change)

The evolution of your mole(s) has become the most important factor to consider when it comes to diagnosing a melanoma. Knowing what is normal for YOU could save your life. If a mole has gone through recent changes in color and/or size, bring it to the attention of a dermatologist immediately.

Acral Melanoma Pictures.

Under the nail bed, this is often referred to as subungual melanoma.

Source: Photos courtesy of Dr. Guowen Wang in the Department of Soft Tissue Cancer, Tianjin Cancer Center, Tianjin Medical University

Ocular Melanoma Pictures.

Medium choroidal melanoma near the optic disc showing blood where the tumor has ruptured through the overlying Bruch’s membrane to form a “collar button”; Source: Photos courtesy of Dr. J. William Harbour of Bascom Palmer Eye Institute

Have questions about ocular melanoma? Read about CURE OM, the MRF’s initiative for ocular melanoma.

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Patient Resources

The MRF is committed to providing the most up-to-date education and support resources for melanoma patients and their loved ones.

Citations

Content last updated: June 1, 2021

  1. National Cancer Institute, Division of Cancer Epidemiology and Genetics

  2. Centers for Disease Control and Prevention

  3. National Cancer Institute, Division of Cancer Epidemiology and Genetics, https://moles-melanoma-tool.cancer.gov/