When should I be concerned about my moles? How dangerous are they?

 

Recently I had a number of teenagers come to the office for their yearly physicals. They had been put on hold because of the Covid pandemic, and now that there was optimism about high school sports opening up after the new year there was a surge in sports physicals.
 

Most often during these examinations the subject of moles came up—when one should be concerned or see a dermatologist about them

 

Moles are caused by skin cells called melanocytes, cells that produce melanin which is responsible for our pigmentation. They grow in clusters and are not evenly spread throughout the skin. Moles are very common. Genetics plays a role in one getting them. By the time a person reaches adulthood, it is common to have at least 10-20. If one has over 50 moles they should see a dermatologist due to possible increased risk for melanoma which is a form of skin cancer. A study out of Australia showed that of the patients aged 15-19 years that had melanoma, over 50% had more than 100 moles.

 

Freckles are common as well. They are the result of an overproduction of melanin from excessive sun exposure. The melanocytes of freckles are evenly distributed throughout the skin and have a genetic predisposition as well. But they are not likely to become cancerous. Freckles are flat whereas moles tend to be raised and are much darker than freckles.
 

There are a number of criteria that would make a mole suspicious and warrant a visit to a dermatologist.

• If a mole grows rapidly in size over a short period of time

• If a mole bleeds or itches

• If there is a color change such as speckling. Or if it becomes darker within the mole itself

• If the borders are ragged or shaggy. Or if there are new moles forming near the border that seem to have been seeded from the mole which is referred to as “mushrooming”

• If there is asymmetry of the mole. One should be able to draw a line through the center and both halves should match. If not, one should see a dermatologist

• If a mole is larger than the eraser of a pencil

 

I have given up trying to figure out which moles a dermatologist feels is a concern. Many times I will refer a patient about a mole that is worrisome. When my patient comes back, the mole is still there…but a different one has been removed. The bottom line is that dermatologists are experts in this area and they know which are concerning. More times than not, they will elect to observe and not remove. They will take pictures and make measurements to establish a baseline. As a parent living with your child and seeing him or her every day, you cannot appreciate the changes that take place because they are so subtle.