In screening for suspicious moles that could potentially be cancerous doctors are taught to use the ABCDEs of a proper skin exam. These are characteristics of a suspicious mole that make it more likely your doctor will want to biopsy and investigate further.

❇️A-stands for asymmetrical. Melanomas tends to be more asymmetrical in shape than normal nevi or beauty marks.

❇️B-stands for border. Are the borders irregular? Irregular borders are more common in melanomas.

❇️C-Color. Is the color not consistent? More variable, darker spots can signs of melanoma as opposed to uniformity in color or shade.

❇️D-Diameter. Is the diameter greater than 6mm? Larger than that can be a sign of melanoma developing.

❇️E-Evolution. Has the mole been stable over a long period of time or has it rapidly started changing? Melanomas are fast spreading and evolve quickly. If you’ve had a mole or beauty mark for a long time and it hasn’t changed it’s less likely to be of concern.

And now it looks like we can add a new letter to the mix: F, for “funny looking” and is part of the new “ugly duckling” sign. The Ugly Duckling, or UD sign stems from the notion of the "signature nevus"—that idea that each person forms a characteristic pattern of melanocytic nevi (moles) based on genetic determinants such as skin phototype.

By encouraging patients to look for cutaneous lesions that break their typical mole pattern, the UD sign may show superior sensitivity and/or specificity for detecting melanoma when compared with the more static ABCDE rules.

In a small informal study conducted at the Mayo Clinic volunteers were trained to look for “ugly duckling” lesions and compared them to volunteers doing standard ABCDE screening. They found a much greater specificity in the group trained to look for Ugly Ducklings in detecting malignant melanomas that in the group trained to look for ABCDE signs alone.

As a patient make sure you are getting regular screenings for suspicious looking moles and keep an eye out for those ugly ducklings. If you have a personal or family history of skin cancer then you need to be even more careful. And remember to always wear an organic, mineral based sun screen, every day!

References:

https://www.ncbi.nlm.nih.gov/pubmed/28964538/

http://www.jaad.org/article/S0190-9622(17)32054-6/abstract