How to Tell When a Mole Needs a Doctor's Opinion

 How to Tell When a Mole Needs a Doctor's Opinion

Most people have at least a few visible moles on their body and they generally don’t cause any problems. Occasionally, however, a mole may be a dangerous form of cancer called melanoma.

Moles: Sometimes More than Meets the Eyes

While moles (or nevi) seem pretty straightforward, there are actually a few different types of moles. The common mole is a harmless flat or raised collection of pigmented skin cells (melanocytes). Most people are familiar with common moles and people with lighter skin can have anywhere between 10-40 common moles. These moles can develop at any time, but usually occur in children and adolescents. Common moles are almost always small and uniform in shape and color, but they can vary in color and size.

Some people are born with moles. These congenital moles can vary in size like a common mole, but congenital moles can be much larger. People with congenital moles are more at risk of developing skin cancer either with the congenital mole or another.

An atypical mole is any mole that displays characteristics different from a common mole. Most often, atypical moles have one or more of the following characteristics: larger than the head of an eraser, a mix of multiple colors or shades of one color, and not uniform (round) in shape. Atypical moles are far more likely to be or become cancerous, but an atypical mole does not always become melanoma.


Melanoma is a dangerous, fast-acting skin cancer that often appears like a mole or in an existing mole. While melanoma moves fast, if you know what to look for you can catch it before it causes any lasting health problems. Melanoma is responsible for a disproportionate number of deaths for a skin cancer. While only about 1% of people will develop melanoma in a given year, roughly 7,000 die from melanoma each year. Caution when you notice a mole changing or developing is highly recommended by dermatologists.

There are some factors that should make you even more cautious about moles. If you are over the age of 30, you are more likely to have melanoma. The reason for this is simple: cumulative sun damage is the number one contributor to your odds of developing skin cancer. Harmful ultraviolet rays in sunlight can cause immediate symptoms (a sunburn), but that damage has the potential to manifest as melanoma and other skin cancers years later. Age plays a factor because time allows more damage to build up. As tanning reached its peak popularity in the early 2000s, the statistics for younger women developing melanoma increased greatly. As a result, melanoma is not just something people get when they’re over 65.

How to Look at Your Moles

Since we know a mole’s appearance can affect our health, dermatologists have come up with some simple ways to identify melanoma in a new or changing mole. The top 5 characteristics to look for have been made into a mnemonic device for easy memorization. Meet the A-B-C-D-Es of melanoma.

A - Asymmetrical: A mole is asymmetrical when its shape is not fairly round. While it’s not always worrying to see a mole that isn’t perfectly round, a mole’s general shape can tell whether melanoma may be hiding within. Does your mole look more like a rectangle or oval than a circle? If so, it’s more likely to be or develop melanoma.

B - Border: The definition of a mole’s outside borders can be an indicator of whether or not melanoma is present. If the mole’s borders are fuzzy or it’s cluster of round shapes, the mole is atypical and could be melanoma.

C - Color: The color of a common mole is usually distributed evenly. If a mole is different colors or shades throughout, it’s more likely to be melanoma.

D - Diameter: If your mole is growing to or formed at a size larger than a pencil eraser or a pea, it is atypical and may be melanoma.

E - Evolving: If you notice any mole change, it’s possible that melanoma is present. If any or all of these attributes listed above have changed in the recent months or weeks, your mole is evolving. This is because melanoma is a cancer, and with all types of cancer it involves the rapid production of natural cells to an unnatural, life-threatening level. In this case, the cells are melanocytes.

So, the short answer to our question is: you should see a doctor if you notice any new or changing moles. Err on the side of caution, because melanoma is highly treatable when caught early, but also highly dangerous. Call a New England Dermatologist if your moles have changed or a new mole has appeared.

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