Atypical Moles

A common mole is a spot on the skin that develops when melanocytes cluster together. Common moles are round or oval, flat or raised, of a single color, including pink, brown, or black, have a well-defined border, and are smaller than a dime in size. Common moles can be found anywhere on the body, including underneath fingernails, and between fingers and toes. A common mole has the potential to become a melanoma.

The primary causes of moles are genetics, sun exposure, immune diseases, and some drug treatments.

About 1 in every 10 Americans is estimated to have at least one atypical mole (3). An atypical mole has an irregular shape, is larger than a common mole, and has poorly defined borders. With features similar to melanoma, atypical nevi have several colors and varying surfaces that could be flat, smooth, or scaly. These dysplastic moles can appear anywhere the skin is exposed to the sun but may also appear in areas not exposed to the sun.

While dysplastic nevi are not melanoma, people with dysplastic nevi are at increased risk for melanoma. The more atypical nevi you have, the greater the chance of developing melanoma. People with atypical moles and a family history of melanoma are at increased risk for melanoma (4). Moles that look atypical should be evaluated by a dermatologist and monitored regularly.

The ABCDEs are the warning signs to evaluate atypical moles at risk for melanoma.

Asymmetry means the shape is different from one side of the lesion to the other. If you drew a line down the middle of the mole, the halves would not be a mirror image of each other.

Borders are irregular, notched, scalloped, or blurred, and are not smooth and even as with common moles.

Colors of dysplastic moles vary, including brown or black, with red, blue, or white spots, unlike common moles, which are typically skin-colored, brown, or black.

Diameter means the size is larger than 6 mm or the size of a bead. However, smaller moles with other danger signs could also be melanoma.

Evolving means the mole changes shape, size, color, or elevation, or another new symptom occurs, such as bleeding, itching, or crusting. Crusting is the most concerning sign.

Melanoma is the most important reason for at-home skin exams and annual skin checks from your dermatologist.

Nevi are typically diagnosed through visual examination, supplemented by a technique known as dermatoscopy. This method aids board-certified dermatologists, such as Dr. Michelle Pennie, in differentiating benign nevi from cancerous lesions. A dermatoscope, a specialized magnifying instrument, enhances diagnostic accuracy, particularly for the early identification of suspicious nevi.

During your annual skin check, your Bliss Dermatology provider will examine you from head to toe. Moles can hide anywhere, including the ears, between the fingers and toes, near the eyes, and in the genital area. If he or she is concerned about a nevus, a biopsy, or small piece of the mole, will be taken and send it to a laboratory for microscopic evaluation. If she finds dysplastic nevi, you will monitor the mole for changes over time and schedule more frequent exams if you notice changes.  However, if you have more than five dysplastic nevi, she will recommend that you have your skin examined on a more frequent schedule. If you have a family history of melanoma, you should have your moles checked more frequently. Discuss a care plan with your provider.