Moles, Skin Tags and Spots: When Should You Show Them to a Physician before an Aesthetic Treatment?

Are moles, skin tags, seborrhoeic keratoses and spots the same thing?

In everyday speech almost any raised patch or dark dot that appears on the skin is called a 'mole'. Yet these are different structures and are dealt with in different ways. The table below is not a diagnostic tool; it only shows what the physician is trying to tell apart during the examination.

It is not always easy to make this distinction by eye. A benign seborrhoeic keratosis can look worrying; by contrast melanoma, a type of skin cancer, can look like a harmless mole or spot. In making this distinction, physicians use an illuminated magnifier called a dermatoscope in addition to the naked eye.

Which moles and spots should be shown to a physician?

There are two simple tools that dermatology organisations recommend to the public. The first is the ABCDE rule, used when looking at a single lesion. The second is the 'ugly duckling' sign, which compares the lesion with the person's other moles.

The 'ugly duckling' sign is based on this observation: a person's moles generally resemble one another; they are like members of one family. A mole that does not resemble the others, that is darker, larger or more irregular than them, or on the contrary simply stands out on its own as different, deserves attention. In a study carried out with specialists in skin diseases, it was reported that assessing moles by comparing them with the person's other moles markedly reduced the number of moles unnecessarily regarded as suspicious, and that all the melanomas in the study were marked as 'different' in this way.

These rules are a screening tool, not a diagnosis. Most lesions that fit the rules turn out to be harmless on examination; and a lesion that does not fully fit the rules may occasionally be a problem. So do not wait for every item to apply before showing a spot you 'do not feel right about'.

Is it an emergency, or can it wait?

A changing mole usually does not require a visit to the emergency department; health services count it among situations that are 'not an emergency but need to be seen by a physician'. On the other hand, melanoma is much easier to treat when it is noticed early. The right attitude lies between the two: being examined without panicking, but without putting it off for months.

For people with many moles, people with fair skin, those with a personal or family history of skin cancer, and those who have had frequent sunburn or used sunbeds in the past, regular skin examinations at the intervals recommended by the physician are also important. The priority of this matter in later life is dealt with in the article “Skin Care and Medical Aesthetics at 50 and Beyond”.

Why are laser, IPL and hair removal not used over a mole?

Laser and intense pulsed light (IPL) are absorbed by melanin, the colouring matter in the skin. Because moles contain dense melanin, they absorb the light strongly. This has two consequences. First, burns, blisters and scarring can develop at the site of the mole. Second, and more importantly, the appearance of the mole changes.

In a systematic review of moles passed over during laser hair removal, shrinkage, lightening or darkening, asymmetry of shape and changes in dermatoscopic appearance were reported in moles. The same review stated that there was no documented case of a mole turning into cancer after laser hair removal, but that long-term data are limited. So the concern is not that laser turns a mole into cancer. The concern is that a mole whose appearance has changed becomes harder to assess in future, and that a real warning sign may be missed.

• During hair removal and light treatments, moles are skipped or protected by covering them.
• If there is a mole that looks suspicious, it is recommended that it be shown to a dermatologist before the procedure.
• Having a mole 'removed by laser for aesthetic reasons' is a separate and debated matter: because laser destroys the tissue, nothing is left to be examined, and some of the mole cells may remain in the skin and regain colour. This is why the decision belongs to the physician who examines the lesion.

The details on hair removal are dealt with in the article “Problems after Laser Hair Removal”, and the concern about cancer in the article “Rumour: Laser hair removal causes cancer — What does the science say?”.

Why is laser or pigment cream inadvisable on an undiagnosed spot?

Not every dark patch taken for a sun spot is a sun spot. There is a type of melanoma (lentigo maligna) that begins as a slowly growing, flat, brown patch on sun-damaged skin, especially on the face, and it can be confused with harmless spots. When the records of 503 patients given this diagnosis over a ten-year period at a cancer centre were reviewed, 37 of them (about 7 per cent) were found to have previously had freezing, laser or lightening cream applied to the same lesion for aesthetic reasons. The researchers concluded that such treatments may delay the diagnosis and, by blurring the borders of the lesion, may make a more extensive operation necessary.

This rate is retrospective data from a single centre and is not a measure of risk for everyone who has a spot lasered. What it shows is simpler: lightening the colour is not making a diagnosis. Laser or cream can reduce the visible pigment of the spot; if the underlying cells remain in place, the problem has only been hidden.

• Before laser, IPL, a peel or a lightening cream is used on a spot, what the spot is must have been established by a physician.
• This is especially important for spots that stand alone, differ from the others, have an irregular edge or vary in shade.
• A spot that comes back or changes shape despite treatment should be reassessed.
• If the physician considers it necessary, a small piece is taken from the spot (a biopsy) for examination; this is not an obstacle that delays the procedure but the condition for the procedure being safe.

Which method is chosen for pigmented spots after diagnosis is explained in the article “Pigment Lasers”.

How are skin tags and seborrhoeic keratoses removed?

Skin tags and seborrhoeic keratoses do not need to be removed for health reasons. They can be removed if they rub and become irritated, bleed, catch on jewellery or clothing, or if their appearance bothers the person. The main methods used by the physician are these:

• Freezing (cryotherapy): the lesion is frozen with liquid nitrogen; within days it crusts over and falls off.
• Removal by heat (cautery) or cutting with surgical scissors or a scalpel: usually done quickly under local anaesthesia.
• Curettage and shave removal: used for superficial lesions such as seborrhoeic keratoses.

Although these procedures seem minor, they are medical interventions. Afterwards a scar, or darkening or lightening of the skin, may remain; this risk is higher in olive and dark skin and, although usually temporary, sometimes may not reverse. In people prone to raised scars this should be discussed specifically; the details are in the article “Scars and Keloids”. A removed lesion is not generally expected to recur in the same place; however, in people who are prone to them, new ones may appear elsewhere.

If a skin tag is growing, hurts or bleeds, or if skin tags rapidly increase in number, show it to a physician before having it removed. Not every outgrowth that looks like a skin tag is a skin tag.

Why are tying off with thread, acid or 'mole removal' cream at home risky?

Ointments, gels, pens and liquids claimed to 'make moles, skin tags and similar lesions fall off at home' are sold online and in some shops. The US Food and Drug Administration (FDA) has stated that there is no prescription or non-prescription medicine it has approved for this purpose and has warned consumers to stay away from these products. The agency says it has received reports of people who developed irreversible skin damage and infection after using these products.

• Burns and scarring: these products may contain salicylic acid in high concentrations or other corrosive substances. They usually do not remove the lesion completely; they can leave scarring and colour change in the healthy surrounding skin. The result, especially on the face, may be more bothersome than the original lesion.
• Infection: infections requiring antibiotic treatment have been reported.
• Delayed diagnosis: when the lesion has been partly destroyed or its appearance has changed, it becomes harder for the physician to tell whether it is a skin cancer. A skin cancer that has not been completely removed can continue to grow.
• The label 'natural' or 'herbal' does not mean a product is safe; such products may also contain corrosive substances.
• Tying off with thread or a strand of hair, or cutting with nail scissors: these carry a risk of bleeding, infection and scarring. Health services advise you not to try to remove a skin tag yourself unless a physician has recommended it.
• The same objections apply to cautery pens and 'plasma' devices used at home.

The risks of other treatments carried out at home are dealt with in the article “Needle-Free Filler Pens and At-Home Treatments”.

Why is a removed mole sent to pathology?

What a lesion is can be said with certainty only by examining the removed tissue under a microscope. This is why, if the physician is removing a mole because of suspicion, the specimen is sent for pathological examination. For lesions with a typical appearance, such as skin tags, the physician decides whether examination is needed; if you are unsure, you have the right to ask why.

This also affects the choice of method. A mole that is cut out can be examined; from a lesion that is vaporised by laser, frozen or burned with acid, no tissue is left to examine. This is also the most important objection to a mole being removed by someone other than a physician, in a beauty salon or at home: what can go wrong is not only a scar but a diagnosis that was never made.

How can you keep an eye on your moles?

• Every few months, look at all of your skin in good light; for the back, scalp, soles of the feet and nails, use a mirror or ask someone close to you for help.
• Photograph the moles you are unsure about with a ruler beside them; follow change by relying on the photograph, not on memory.
• Do not let a 'harmless' answer from phone apps and artificial intelligence tools take the place of an examination; these tools can be wrong.
• Protect yourself from the sun and do not use sunbeds; ultraviolet rays increase the risk of skin cancer. The details are explained in the article “Sunscreen Guide”.
• Even if you are not asked at the place where you go for an aesthetic treatment, point out the moles and new spots in the treatment area yourself.

The aim of this article is not to cause worry. The vast majority of moles and skin tags cause no problems throughout life. The only thing that needs to be done is to get the order right: diagnosis first, aesthetics second.