Most of us live with moles for years without thinking about them. They are on the back, arms, chest, legs, scalp, or feet, and sometimes only a spouse, hairdresser, or doctor notices a small change. In most cases there is no reason for concern, but with skin there is an important rule: A new change, an unusual lesion, or a wound that does not heal are not things you should explain on your own.
A mole is an accumulation of pigment-producing cells in the skin. It can be flat or raised, light or dark, small or large. Some people have few moles, while others have dozens. Some moles exist from childhood, while others appear during life. Sun exposure, genetics, fair skin, family history, past sunburns, and a large number of moles can affect the risk of developing suspicious lesions.
The main concern is melanoma, a dangerous type of skin cancer originating in pigment cells. Melanoma can develop from an existing mole, but it can also appear as a new lesion on skin that previously looked normal. It can appear in sun-exposed areas, but also in less expected places, such as the feet, under the nails, on the scalp, or in areas hardly exposed to the sun. Therefore, a skin examination does not end with a quick look at the face and hands.
The most familiar rule for identifying a suspicious mole is the five-sign method. The first sign is asymmetry: If you divide the lesion in two, the two halves do not look alike. A regular mole tends to be more symmetrical, whereas a suspicious lesion may look unbalanced, as if one part of it grew differently.
The second sign is an irregular border. A benign mole usually has relatively smooth and clear borders. A suspicious lesion can have jagged, blurred, notched, or uneven borders. This does not mean every imperfect border is melanoma, but a change in the border or a border that looks "smeared" into the surrounding skin warrants an examination.
The third sign is color. A mole uniform in light or dark brown color is less concerning than a lesion with several shades: Brown, black, reddish, bluish, white, or gray. Multiple colors within the same lesion, especially if it is new or changing, is a sign that should be shown to a dermatologist. A mole that turns darker quickly also requires attention.
The warning signs to watch for
The fourth sign is diameter. In the past, emphasis was placed on lesions over 6 millimeters, roughly the size of a pencil eraser, but it is important to know that melanoma can also be smaller. Therefore, diameter is only part of the picture. A small mole that changes, bleeds, or looks different from all other moles on the body can be more important than a large mole that has been stable for years.
The fifth sign, and sometimes the most important, is evolution. Any mole that changes in size, color, shape, height, feel, or behavior requires an examination. New itching, bleeding, recurring scab, pain, a wound that does not heal, or a lesion that becomes more prominent are signs that cannot be diagnosed from home. Dermatologists also refer to the "ugly duckling" rule: A single lesion that looks different from all other lesions on the body, even if it does not precisely meet all the signs, needs to be checked.
Besides melanoma, there are other types of skin cancer, such as basal cell carcinoma and squamous cell carcinoma. They are more common than melanoma, and in most cases less fatal, but they also require treatment. They can appear as a wound that does not heal, a shiny bump, a scaly red patch, an area that bleeds repeatedly, or a rough lesion on sun-exposed skin. People tend to think it is a "small wound" or "dryness," but if it does not disappear, it needs to be checked.
Who is at higher risk? People with fair skin, light eyes, freckles, a history of sunburns, tanning bed use, multiple moles, atypical moles, a personal or family history of melanoma, immunosuppression, or prolonged work in the sun. But skin cancer can also appear in dark-skinned individuals, and it is sometimes discovered later in them precisely because suspicion is lower. Therefore, any suspicious change requires an examination, regardless of skin color.
Who is most at risk?
A self-examination once a month can help. Stand in front of a mirror, check the face, ears, neck, chest, abdomen, hands, between the fingers, legs, feet, and nails. Using a hand mirror or another person, also check the back, nape of the neck, scalp, and buttocks. It is advisable to photograph moles that concern you in good light, with a date, to identify real change over time. There is no need to get obsessed, but you should know your personal skin map.
A dermatologist uses a dermatoscope, a device that allows seeing structures in the lesion that are not visible to the naked eye. If the lesion is suspicious, it may be removed and sent for pathological examination. This is the only way to determine with certainty whether it is a malignant lesion. Burning, scraping, or cosmetic treatment of a suspicious lesion without a diagnosis may delay diagnosis, so a changing mole is not removed at a beauty salon nor treated independently.
Prevention is still important. Excessive sun exposure, and especially sunburns, increases the risk of cumulative skin damage. It is recommended to avoid exposure during peak hot hours, use broad-spectrum sunscreen, wear a hat, wear protective clothing, and take special care with children. Skin burned in childhood remembers the damage years later. Tanning beds are not a safe alternative to the sun, and they increase the risk of skin damage.
When to seek an examination? When there is a new and strange mole, a change in an existing mole, a lesion that bleeds, itches, hurts, scabs over and returns, a wound that does not heal within a few weeks, a new dark stripe under a nail, or a lesion that looks different from all other lesions. In such cases, do not wait for the annual appointment and do not try to reassure yourself with a picture from Google. Schedule an examination with a dermatologist.
Most moles will not turn into cancer. But the great advantage of skin is that it is visible to the eye. The body gives us the opportunity to see a change in time, provided we are willing to look. A brief check in front of a mirror and a medical checkup when needed can make the difference between a lesion removed early and a disease discovered late.