Malignant melanoma may look like a mole that has certain characteristics, such as being asymmetrical, having an uneven border or color and changing in size with time, states the National Institutes of Health's National Cancer Institute. Although most moles that appear on the skin are harmless, it is important to know the features that dermatologists use to detect skin melanoma or a cancerous mole, which is the ABCDE rule, notes Healthline.
Skin melanomas start in the cells called melanocytes that produce melanin. Melanomas most often appear like moles on any part of the body, but they can also develop in the eyes, notes the National Cancer Institute. However, people can detect a cancerous skin mole by following the ABCDE rule, in which the letter A refers to a mole's asymmetrical shape, B is its border, C stands for color, D is the diameter and E stands for the mole's evolution through time.
A cancerous mole may not appear the same or symmetrical on both of its sides as does a normal mole. The border or edges of a normal mole is usually regular in shape, whereas a malignant mole has an irregular or jagged border shape, states the American Cancer Society.
A malignant mole can have varying shades or mixes of the colors brown, gray or black. A benign mole is usually one solid color throughout that can range from tan to black. If the mole's diameter increases or it bleeds, itches, or oozes over time, then it is evolving. The typical size of a regular mole is about 1/4 of an inch. When a person notices any of these changing features in a mole, he should see a doctor for a diagnosis.