Note: The description below is provided for general information only and is not intended for self-diagnosis.
Moles, or nevi, are very common growths, which may be pigmented (brown) or skin-toned. They may occur at birth or later in life. Those present at birth are also known as congenital moles and often have one or more hairs emerging from them. Moles often start out flat and may slowly rise over the years.
When examining moles, care must be exercised to distinguish between benign moles and their malignant counterpart, malignant melanoma. Melanoma is a potentially very dangerous skin cancer, especially if not caught early in its evolution. Though some melanomas may arise within existing moles, others appear on previously unaffected skin.
What Are the ABCDE’s?
Over the years, several criteria have been developed to attempt to separate moles from melanoma. Though such a separation may occasionally be difficult even for experts in the field, these criteria, also known as the ABCDE’s, provide useful guidelines to help determine which lesions should be monitored more closely or possibly biopsied for microscopic examination.
A, B, and C: Asymmetry, Borders, and Color
“A” stands for asymmetry. Unlike benign moles, melanomas often exhibit asymmetry, meaning that one side of the lesion does not look like the other.
“B” stands for borders. Melanomas frequently have irregular or jagged borders, while benign moles typically present with sharper, more rounded borders.
“C” stands for color. Most benign moles are either skin-toned or contain only one color. Black or very dark brown color, especially when compared to other moles on the body, should raise suspicion of possible malignancy. Beware, however, that some melanomas, the so-called amelanotic melanomas, are also skin-toned or reddish, with no conspicuous brown or black pigment.
D and E: Diameter and Evolving
“D” stands for diameter. Benign moles are often smaller, most commonly less than 6 millimeters in diameter, about the size of a pencil eraser. This is not always true, however, as some congenital nevi may be larger than 6 millimeters, while melanomas may start off quite small. Nonetheless, a larger lesion size, especially when a new lesion is noted, should cause suspicion.
“E” stands for evolving, or changing. This is probably the most important criterion, as melanomas continue to evolve, meaning they may increase in size or change in color, whereas their benign counterparts should typically remain the same over time. In addition, the appearance of new moles should raise suspicion, especially in anyone over 40 years of age.
Additional Warning Signs
Additional suspicious characteristics may include bleeding or other symptoms arising within a mole, as well as a white halo-like rim appearing around a pigmented lesion. The latter occurrence may also be benign, as in the so-called halo nevus, though professional examination by a dermatologist is essential.
Though amelanotic melanomas can be more difficult to recognize clinically because they lack dark pigment, the criterion of change over time often still applies.
When to See a Dermatologist
While these criteria are useful, they are intended as guidelines only and are not meant for self-diagnosis. Any suspected pigmented, or occasionally skin-toned, lesion should be brought to the attention of a dermatologist, who can then determine whether further evaluation or biopsy is necessary.
Frequently Asked Questions
What does the “A” in ABCDE stand for?
“A” stands for asymmetry, meaning one side of the lesion does not match the other.
Does every mole larger than 6 millimeters need to be removed?
No. Some benign moles, especially congenital nevi, may be larger than 6 millimeters. Size alone does not determine whether a lesion is dangerous.
What is the most important ABCDE criterion?
“E” for evolving, or changing, is often considered the most important warning sign.
Can melanoma be skin-toned instead of dark?
Yes. Some melanomas, called amelanotic melanomas, may be skin-toned or reddish and may not contain obvious brown or black pigment.
Should I use the ABCDE’s to diagnose myself?
No. The ABCDE’s are general guidelines only and are not intended for self-diagnosis. Suspicious lesions should be evaluated by a dermatologist.
If you have a mole or pigmented lesion that is changing, unusual, or concerning, schedule an evaluation with Dr. Berlin for professional assessment.