When a spot on the face should be seen by a doctor first

Most spots on the face are benign: sun spots, melasma, acne marks, freckles. It is therefore natural to think of them as an aesthetic problem and to look straight away for a treatment to lighten them. But a small percentage are not harmless, and some of the most dangerous skin lesions begin, precisely, by looking like "just another spot".

This article is not meant to frighten. It is meant to explain the most important rule of any treatment for dark spots: first the diagnosis, then the treatment. And to help recognise the signs that justify a medical examination before any peel, laser or lightening cream.

Why the face deserves special attention

The face is the part of the body that receives the most sun over a lifetime. It is exposed every day, in every season, walking, driving, on a café terrace, even when you are not "sunbathing". This chronic, cumulative exposure is the main risk factor for the most common skin cancers.

According to the Portuguese Skin Cancer Association, around 13,000 new cases of skin cancer arise in Portugal each year, of which more than a thousand are melanomas. The vast majority of the rest are basal cell and squamous cell carcinomas, which appear mainly in exposed areas, with the face first among them.

The good news is that skin cancer is among the most visible and most treatable when caught early. In melanoma, the likelihood of cure depends mainly on the thickness at the time of diagnosis: thin melanomas, detected early, have an excellent prognosis. The problem is that, on the face, many of these lesions are flat, grow slowly and are easily mistaken for benign spots the person has had for years. That is where a medical eye makes the difference.

Lesions that disguise themselves as a spot

These are the lesions that most often pass for a "spot" or "dry skin" on the face and that require a medical diagnosis.

Lentigo maligna: the melanoma that looks like a sun spot

Lentigo maligna is a form of melanoma in situ (still confined to the epidermis) that typically appears on the face of people over 50 to 60, with a lot of accumulated sun. It is flat, brown, grows very slowly, over years, and is therefore easily mistaken for an ordinary solar lentigo. If left untreated, it can become invasive (lentigo maligna melanoma).

Clues that raise suspicion: a spot that keeps widening, with several shades of brown, darker or greyish areas, irregular borders, or that is clearly larger and different from your other sun spots.

Nodular melanoma and other melanomas

Not all melanomas are flat spots. Nodular melanoma appears as a small raised, firm nodule that grows over weeks to months, sometimes without pigment (skin-coloured or pinkish). It does not fit the ABCDE rule well and so there is another rule for it (see below; Kelly et al., 2003).

Actinic keratosis: the "dry skin" that will not go away

Small rough areas, like sandpaper to the touch, pink, reddish or brownish, in highly exposed areas (forehead, nose, cheekbones, bald scalp, lower lip). They are often easier to feel with a finger than to see. They are pre-malignant lesions: a small proportion may progress to squamous cell carcinoma. There are also pigmented forms, which can be mistaken for sun spots.

Basal cell carcinoma: the "spot" that does not heal

It is the most common skin cancer and appears mainly on the face. It grows slowly and rarely spreads, but can destroy the surrounding tissue if left untreated. It presents as:

• A small pearly, translucent nodule, with small vessels at the surface.
• A "spot" or sore that bleeds easily, forms a crust, seems to heal and opens again.
• A pink, flat, slightly shiny patch that does not go away.
• Pigmented forms, brown or greyish, more frequent in darker skin.

Squamous cell carcinoma

A rough lesion, with a crust or thick scale, sometimes painful, which grows over weeks to months. It appears in exposed areas, on the lips and ears, and has a greater potential to spread than basal cell carcinoma.

Other situations that call for assessment

• Spots that appear suddenly and in large numbers.
• Spots associated with other symptoms (tiredness, weight loss, changes in other areas of the skin or in the mucous membranes).
• Spots that appeared after a new medicine.
• Pale or white patches that spread (they may correspond to vitiligo or a superficial fungal infection, among other causes).

Warning signs: the rules that help

The ABCDE rule

Created to help recognise melanomas in moles and pigmented spots (Abbasi et al., 2004):

Of all of them, E is the most important: a spot that changes always deserves examination.

The "ugly duckling" sign

In the same person, moles and spots usually resemble each other. A lesion that is clearly different from the others (darker, larger, with another shape or colour) should be examined, even if it does not meet the ABCDE criteria (Grob and Bonerandi, 1998).

The EFG rule, for raised lesions

For nodules that grow quickly, such as nodular melanoma:

• Elevated
• Firm to the touch
• Growing, that is, growing progressively for more than a month

Signs that do not depend on colour

These rules help decide when to see a doctor. They are not for ruling out a cancer: early lesions may have none of these signs, and many benign lesions have some.

Who should be more watchful

The risk of skin cancer is higher in people who have:

• Fair skin, light eyes, red or blonde hair, that burns easily and tans poorly.
• A lot of accumulated sun exposure: outdoor work, outdoor sports, living by the sea.
• History of sunburn, especially in childhood and adolescence.
• Use of sunbeds.
• Many moles (more than 50) or atypical moles.
• Personal or family history of melanoma or other skin cancers.
• Age over 50.
• Immunosuppression, for example in transplant recipients or people taking immunosuppressant medicines.
• Many sun spots and actinic keratoses, which are markers of accumulated sun damage.

Darker skin has a lower risk, but is not immune. In people with darker skin, melanomas appear more often on the palms, soles and nails, and are often diagnosed later.

Why a spot is not treated before diagnosis

It may seem excessive caution. It is not. There are three concrete reasons.

1. The treatment may erase the clue without erasing the disease. Lasers, pulsed light, peels and lightening agents act on pigment. On a benign spot, that is the goal. On a lentigo maligna or a melanoma, the pigment may disappear at the surface while the abnormal cells remain. The lesion "comes back" months later, with the diagnosis already delayed.

This is documented. A case published in the Medical Journal of Australia in 2017 describes a 56-year-old woman with a pigmented patch on her cheek, growing for 18 months, treated with a laser at an aesthetic clinic with no prior clinical or dermoscopic assessment (Bala et al., 2017). The pigment disappeared completely, but the lesion reappeared over the following year. A biopsy confirmed a lentigo maligna. The authors stress that it has not been proven that lasers cause melanoma, but that treating undiagnosed lesions may delay diagnosis and worsen the prognosis. Similar case series have been described in other countries (Delker et al., 2017).

2. Treatment can make later diagnosis harder. After a laser or a peel, the lesion shows healing changes and residual pigment that make dermoscopy and even analysis of the biopsy harder to interpret. People even speak of "pseudomelanoma", treated lesions that come to look like melanomas without being so, and the opposite can also happen.

3. The treatment may be the wrong one. An actinic keratosis needs specific medical treatment; a basal cell carcinoma needs surgery or other targeted therapy. No lightening cream or aesthetic peel replaces that, and lost time counts.

That is why, in responsible practices, any treatment for dark spots begins with examining the lesion. If anything raises doubts, the aesthetic treatment is put on hold until there is a diagnosis. See how a proper treatment unfolds in Chemical peel: what to expect on the day, during the peeling and in the following weeks.

What happens at the consultation

Many people put off the appointment for fear of what it involves. In most cases it is simple, quick and painless.

• History. How long the spot has been there, whether it has changed, whether it hurts, itches or bleeds; history of sun, sunburn, sunbeds; cases of skin cancer in the family; medication.
• Examination with the naked eye, in good light, comparing the lesion with the others (the doctor will often also examine other areas of the body).
• Dermoscopy. A dermatoscope is a magnifying lens with its own light, placed against the skin, which makes it possible to see structures invisible to the naked eye. It significantly improves the ability to tell benign from malignant lesions, compared with simple observation (Vestergaard et al., 2008). It does not hurt and takes seconds to minutes.
• Follow-up photography, for lesions that are not suspicious but are worth monitoring. Comparing images over months is one of the most effective ways of detecting changes.
• Biopsy, if there is doubt. A small fragment or the whole lesion is removed, under local anaesthetic, and the tissue is examined under the microscope. It is the only test that confirms the diagnosis with certainty.

In the end, there are three possible scenarios: the lesion is benign and can be treated aesthetically if you wish; the lesion should be monitored and reassessed; or the lesion needs a biopsy or medical treatment. In any of them you leave the consultation knowing what you have.

In Portugal's National Health Service (SNS), the family doctor can examine the lesion and refer to dermatology when necessary.

Self-examination and prevention

How to monitor the skin of the face at home

• Once a month, in good natural light, facing the mirror.
• Check the forehead, temples, eyelids, nose (including the sides), cheekbones, lips, chin, ears (front and back) and neck. Use a hand mirror for the side areas.
• Run your fingers over the skin: actinic keratoses are easier to feel than to see.
• Photograph the spots you want to monitor, always with the same light and distance, and compare every 3 months.
• If the scalp is exposed (baldness), include it, with someone's help.

Prevention

• Broad-spectrum sunscreen, SPF 30 or higher (50 on fair skin or with a history of skin cancer), every day, applied in sufficient quantity and reapplied outdoors. See Tinted sunscreen: how to choose and how to apply.
• A wide-brimmed hat and sunglasses.
• Avoid the hours of greatest radiation, especially between 12 and 4 pm in summer.
• Do not use sunbeds.
• Take special care to protect children.
• See a dermatologist regularly if you belong to a risk group.

At Luxmed, any treatment for dark spots begins with examining the lesion. If a spot raises doubts, it is not treated: it is referred for medical assessment. Only once its benign nature is confirmed is an aesthetic plan defined.

This article is for information purposes and does not replace a medical consultation. If you have a lesion that has changed or that worries you, see your family doctor or a dermatologist.

Frequently asked questions