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The ABC’s of Melanoma Detection

The ABC’s of Melanoma Detection

Melanoma DetectionSkin cancer can be a serious condition, especially if it is not treated early on. Fortunately, many cancerous melanomas tend to differentiate themselves from harmless moles, and marks that may indicate skin cancer can be relatively easy to spot if you know what to look for. “Many melanomas are asymmetrical, have unusual borders and colors, are larger than moles, and are likely to change their size and appearance over time,” shares Dr. Aron Gewirtzman, a board-certified dermatologist at Sanova Dermatology in Austin, Texas. Here is an overview of the most common things to look for that differentiate melanomas from average moles: 


Melanomas tend to stand out from regular moles because they are often asymmetrical and irregularly shaped. Many harmless moles are relatively round to oval and tend to have a mirror image when an imaginary line is drawn through the mole… However, drawing an imaginary line through a lesion that has a high probability of being cancerous will show differences on either side of that line.


“Moles often have relatively smooth, even edges, while melanomas can be much more irregular,” states Dr. Gewirtzman. In addition to asymmetrical shapes, these marks tend to have notched, scalloped, blurry, or other rough edges that do not form a smooth border with the surrounding skin. They can also pull away from the skin more than moles and become rougher or bumpier overall, especially on the edges. This can be a particularly reliable early sign of skin cancer, as unusual borders are often the most prevalent when the melanoma emerges and is just starting to grow.


Color can be another major indicator that a mark may require further attention. Most harmless moles tend to be one to at most two relatively moderate shade(s) of brown throughout the entire lesion, while melanomas often consist of multiple colors. “Melanomas are more likely to consist of a variety of shades of light and dark brown and may include tan or black patches,” Dr. Gewirtzman notes. Red, blue, and other colors that are typically not seen in moles can also appear in cancerous marks.


“Most moles stay quite small, but skin cancers can grow much larger,” Dr. Gewirtzman shares. Lesions that are larger than 1/4 inch (6 millimeters), or larger than the approximate diameter of a pencil eraser, are somewhat more suspicious for skin cancer, while most harmless moles are smaller.  However, early melanomas can be smaller than these guidelines, and any small marks that match other common signs of skin cancer (such as those listed above and below) should also be taken into consideration.  


Finally, marks that continue growing or changing over time may indicate possible skin cancer. While regular moles usually don’t disappear, they are also unlikely to get larger or otherwise evolve, particularly in adults. Melanomas are more likely to keep growing, and they can also change colors and shapes, bleed, become crusty, or evolve in other ways. “While older moles that you’ve had for years or even decades tend to be less likely to change, this criteria can be especially important if you notice new skin marks you don’t recognize that evolve quickly,” urges Dr. Gewirtzman.

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At Sanova Dermatology, we prioritize helping our patients take steps to avoid skin cancer and other serious skin conditions, as well as to recognize and act upon possible signs of skin cancer as early as possible. Although none of these signs automatically indicate skin cancer, lesions that meet these guidelines should be considered potentially serious and evaluated as soon as possible to receive a diagnosis while they are easier to treat if needed. Contact us today with any questions you have about common signs of skin cancer or to schedule an appointment.