Nevi

Nevi – “Moles”

• Nevi are the most common benign lesions that appear on the skin.
• They may be present at birth, but they usually develop during the first decades of life.
• Their appearance is associated with genetic predisposition, but it is also triggered by prolonged exposure of the skin to solar radiation, which is why they multiply at older ages.

Nevi – Categories

Depending on whether they are completely benign or may potentially develop into malignancy, nevi can be divided into two main categories:

I. Common nevi or “moles” and

II. Dysplastic nevi.

Common nevi or “moles”

• Common nevi have a smooth border and a circular or oval shape with clearly defined boundaries.
• They appear as small brown or dark-colored spots or are the same color as the skin.
• They are usually flat, but quite often they may protrude a few millimeters above the surface of the skin.
• A middle-aged adult may have between 10 and 20 common nevi.
• Their size is smaller than 6 millimeters.
• They usually appear on areas of the body exposed to the sun, such as the face, arms, back and shins.

Depending on the type of skin cells from which they originate, common nevi may be:

1. Melanocytic nevi
2. Dermal nevi
3. Junctional nevi
4. Compound nevi
5. Sebaceous gland nevi
6. Eccrine gland nevi
7. Apocrine gland nevi
8. Hemangiomas
9. Skin appendage nevi

The most common types are melanocytic and dermal nevi. Melanocytic nevi have a dark brown or black color and take their name from the large number of melanocytes they contain. Dermal nevi originate from cells of the dermis and are usually skin-colored or slightly brownish.

Common Nevi or “Moles” – Are They Dangerous?

Common nevi are asymptomatic skin lesions. They have a stable morphology and their characteristics do not change over time.

On their own, they do not pose a threat to health. However, there is a possibility that they may develop into dysplastic nevi, which may lead to malignant melanoma. Malignant melanoma can be life-threatening.

When someone notices a change in a nevus regarding its size, shape, color or texture, they should visit a doctor.

If there is suspicion that a nevus is developing into a dysplastic nevus or melanoma, it must be surgically removed for preventive or therapeutic reasons.

Dysplastic Nevi – What Are They?

Dysplastic nevi are also known as atypical nevi. They are skin lesions that closely resemble melanoma but are not melanoma. They occur in approximately 5-12% of Caucasian individuals.

Today, they are considered precancerous conditions, as they may develop into melanoma over time.

Unlike common nevi, they are usually asymmetrical, with an irregular shape and uneven borders.

Their size is greater than 6 millimeters, and they often display two or more colors, with prominent black, brown and reddish areas.

They are usually located on the back, chest, abdomen and limbs, meaning areas of the body that are not exposed to the sun. However, if they are exposed to sunlight, it is believed that their transformation into melanoma is more likely.

Dysplastic Nevi – Are They Dangerous?

Yes. They are dangerous.

The more dysplastic nevi someone has on their skin, the greater their risk of developing malignant melanoma. If someone has more than 50 common nevi and there is a family history of melanoma, they are at a significantly greater risk of developing dysplastic nevi and consequently malignant melanoma compared to the general population.

Dysplastic or Atypical Nevus Syndrome

Individuals who have:

1. one or more nevi larger than 8 millimeters
2. more than 50 nevi
3. one or more dysplastic nevi

have a higher likelihood of developing malignant melanoma at some stage of their lives compared to the general population.

Dysplastic Nevi – Prevention Advice

If there is a strong suspicion that someone has suspicious dysplastic nevi, the nevi should be removed and biopsied. If the nevi are proven to be dysplastic, the patient should:

1. perform regular self-examinations
2. be examined by a doctor every 6 or 12 months
3. undergo mole mapping of the remaining nevi
4. have any additional suspicious nevus that appears in the future removed
5. avoid sun exposure
6. use sunscreen daily and reapply it several times throughout the day
7. avoid sunbathing and artificial tanning, such as solarium use.

Nevi – When Should the Patient Visit a Doctor?

A patient visits a doctor to remove a nevus either for aesthetic reasons or because the nevus is suspicious.

If a nevus is deeply pigmented or protrudes above the skin, we may prefer to remove it for aesthetic reasons, since the scar from the procedure is almost invisible in most cases.

On the other hand, if a nevus is suspicious for malignant transformation, this is also a reason to visit a doctor.

When Is a Nevus Considered Suspicious?

A nevus is considered suspicious when there is concern that it may be, or may develop into, malignant melanoma. This applies if a nevus:

1. is deeply pigmented, meaning it has a dark brown, blue or black color
2. is asymmetrical

• has blue, red or white areas

1. is located on the palms or soles
2. causes itching
3. is painful

• bleeds
• develops an ulcer or serous discharge

1. develops swelling or crusting
2. CHANGES ITS CHARACTERISTICS.

Nevi – Surgical Removal and Histological Examination / Biopsy

Whenever we remove a nevus or a skin lump, we always send the surgical specimen for biopsy and “do not throw it in the bin”.

It is critically important for the patient’s health to determine whether the nevus is common, dysplastic, melanoma or something else.

Depending on the biopsy results, we can determine the appropriate treatment and assess the prognosis of the case.

Nevi – Prevention / Prognosis

Regarding common nevi, there is no reason for concern. If a nevus has a smooth border, is smaller than 6 mm, has a brownish color, etc., there is no reason to remove it except for aesthetic purposes.

On the other hand, if someone has atypical or dysplastic nevus syndrome or has many nevi on their skin, they should undergo regular dermatological examinations and mole mapping.

If one or more of the examined nevi display dysplastic characteristics, the sooner they are removed, the safer the patient is in terms of preventing their transformation into malignant melanoma. In these cases, complete cure is achieved, since once the nevus is removed, it cannot develop into melanoma.

Nevi – What We Should Keep in Mind

Many times, patients notice changes in the characteristics of a nevus that may be suspicious for malignancy, become afraid and postpone visiting a doctor.

There is an “urban myth” that says that “if you remove a mole that is growing or becoming darker, something bad will happen and you will die. The mole will leave and spread somewhere else…”

This is COMPLETELY INCORRECT. The exact opposite is true:

You are not at risk if you remove a suspicious nevus. You risk losing your life if the suspicious nevus is dysplastic or melanoma and you do not remove it in time. If you delay and the nevus is eventually found to be melanoma, it may metastasize and become fatal.

On the contrary, if the suspicious nevus is examined by a doctor and surgically removed in time, we can speak of a CURE, even if the lesion is an early-stage malignant melanoma.

When the patient delays visiting a doctor to have a suspicious nevus examined, valuable time is lost. During this time, a dysplastic nevus may develop into melanoma or an early melanoma may worsen.

For this reason, in cases of suspicious nevi, it is vital to undergo an immediate examination by a dermatologist or Plastic Surgeon, meaning doctors who specialize in skin conditions, have the appropriate experience and can provide the most suitable solution.