Complex pigmented nevus. Melanocytic nevi of epidermal origin

Pigmented nevus is a skin disease. This condition is benign and occurs quite often. In the literature you can see the names “noncellular” and “melanocytic” - these are synonyms, we are talking about the same process.

Noncellular nevus is any congenital disease associated with the proliferation of nevocytes. These are skin cells in which the pigment melanin accumulates. They are very similar to melanocytes, but do not have processes and are less susceptible to the regulatory influences of hormones and other active substances. Nevus cells include round nuclei, their ability to divide is low. Externally, nevi may look like this:

• flat spots that blend into the skin;
• Maculae – spots raised above the surface of the skin;
• dome-shaped tumors or papillomas resembling a wart.

Many researchers believe that pigment formations do not arise during life, but only appear under the influence of certain factors, primarily sunlight. Infants have almost no moles, but in teenagers they are very common. A young person can have up to 40 birthmarks on his skin. With age they fade, disappear, and by old age they are practically absent.

These formations are found in most people. The number of their types is very large. According to WHO recommendations, there are:

• border;
• difficult;
• intradermal;
• spindle cell (epithelioid);
• nevus formed by balloon-shaped cells;
• halonevus;
• giant pigmented nevus;
• involutional (fibrous nasal papule);
• blue and checkered blue.

Types of pigmented nevus formations

Let us dwell in more detail on the features of the most common or most dangerous types.

Border

Borderline pigmented nevus, synonymous with junctional nevus, is the initial stage of the development of skin lesions. It is localized in the uppermost layer of the skin - the epidermis. The formation is congenital or acquired. It often develops in childhood and adolescence, localizing on the palms or soles. Microscopic analysis reveals well-defined clusters, called nests, of nevocytes in the lower epidermal layer at the border with the dermis, hence the name. This type is melanoma-dangerous because it can often degenerate into a malignant tumor.

It is a flat pigment formation. For a long time, pigmented nevi are small in size - up to 3 mm, which gives a person the impression that he has had these spots since birth. In some cases, borderline nevi begin to grow rapidly - 1 mm per year, growing in a few years to a size of 5-6 mm. With such a significant increase in the spot, it is necessary to show such a growing mole to an oncologist. It can transform into a dysplastic nevus, a precursor to skin cancer.

Intradermal

The most common form of pigment spots is intradermal pigmented nevus. It is otherwise called a “resting”, inactive, mole or birthmark. It is characterized by a variety of shapes and colors. A mole is the most common benign formation. It has the appearance of a flat plaque with a diameter of up to half a centimeter, any shades of brown, evenly colored, with a dense texture, rounded shape and clearly visible boundaries. The outer layer of such a formation can be convex, in the form of a wart or a hemisphere. In this case, a papillomatous melanocytic pigmented nevus of the skin is formed.

Nevocytes are located deep in the dermis, its middle and lower layers, forming clusters there. The cells have different shapes and are quite large in size. If they have small nuclei arranged in the form of rosettes, this confirms the benign nature of the formation. Intradermal pigmented nevus may be visible at birth or appear at an early age.

Difficult

Such a nevus is localized both in the upper layer of the skin - the epidermis, and in the middle - the dermis. It is determined on the surface of the skin in the form of a protruding plaque or papilloma (wart). Nest accumulations of nevocytes are located at the point of contact of the upper and middle layers of the skin. If they begin to spread deeper into the thickness of the dermis, they say that the nevus is maturing. This is a benign process.

Neocytes lying in the upper layer of the skin are less mature, which increases their potential for malignancy. They are quite large, have a cubic shape, synthesize melanin and form clusters in the form of nests. Mature nevocytes lie in the deep layers; they are smaller and accumulate less melanin, so their cytoplasm is lighter. They grow with the formation of cords.

The most mature nevocytes are located in the middle of the neoplasm; they have a spindle-shaped, elongated shape. These cells form bundles that resemble peripheral nerve tissue.

Complex nevi in ​​the form of papillomas or polyps usually contain many vessels.

Pigmented nevi

Other types

Balloon nevus

Rarely encountered formation. It is characterized by huge cells with light cytoplasm compared to ordinary nevocytes. Under a microscope, they resemble inflated containers, or balloons, hence the name. They can be located intradermally, but sometimes this type is complex - the cells lie in two layers of skin.

Halonevus or Setton's nevus

It appears as a hyperpigmented (dark) area of ​​skin surrounded by a lighter (depigmented) surface. Sometimes it disappears without any external influence, after which a discolored spot remains on the skin. This formation is often localized on the back of young people and children. Clusters of nevocytes lie in two layers of the skin. A feature of this condition is the accumulation in the area of ​​nests of immunocompetent cells - lymphocytes and macrophages, as if infiltrating the nevus focus with the formation of an inflammatory infiltrate. Immune cells gradually destroy nevocytes - this explains the zone of depigmentation around the spot. Over time, nevocytes disappear under the influence of immune cells. This type of pigment formation is not melanoma-hazardous.

Often refers to a giant form. A giant nevus is located on any part of the body, including the scalp. Its cells grow in the thickness of the dermis and form extensive clusters in it. Such a formation has a high risk of transformation into a malignant tumor (from 2 to 10%).

Spindle cell or epithelioid nevus

It is observed mainly on the face. Its other names are juvenile melanoma or Spitz nevus. The formation looks like one flat or hemispherical nodule. Sometimes it has a surface covered with papillae - papillomatosis. The color of the formation ranges from pink to dull yellow. Around the nodule, dilated small vessels are often visible -. Transformation into an atypical form rarely occurs, although upon histological analysis (under a microscope) such a formation is similar to a malignant skin tumor at the beginning of its formation. Nevocytes occur in the form of rounded and elongated clusters. The cytoplasm of these cells is light because they usually do not contain melanin. In the underlying part of the formation, deep in the dermal layer, the cells become spindle-like. Around them there are many blood vessels from which red blood cells sweat and inflammatory infiltration.

Blue nevus

Otherwise called the Mongolian spot. The cells lie deep in the middle layer of the skin - the dermis. They have no connection with the epidermis. The deep location of nevocytes causes the external effect - the blue color of the spot. The lesion is located on the face, torso, skin of the lower back and hands in the form of single spots of a fairly regular round shape of blue or gray color, with a well-defined border. Such pigmented nevi are invisible above the surface of the skin or rise slightly above it. They become malignant in rare cases. During microscopic examination, in the deep layers of the skin, including subcutaneous fatty tissue, thin branching cells are found - a special type of nevocytes, which contain a lot of the coloring substance - melanin.

Cellular blue nevus is formed by large spindle-shaped cells and an infiltrate consisting of immunocompetent cells - lymphocytes. There is little melanin in it.

Halonevus or Setton's nevus;
Blue nevus

Dysplastic nevi

Any pigmented formation can degenerate into a tumor with signs of malignancy (uncontrolled growth, possibility of metastasis) -. The risk of such transformation is especially high if there is a dysplastic pigmented nevus.

The link between hyperpigmentation and skin cancer has been discovered for almost 200 years, but it wasn't until 1978 that the true precursor to melanoma was found. Such formations (dysplastic nevi) are otherwise called VK moles (after the letters with which the surnames of the very first families studied then began). They are larger than normal birthmarks, their diameter can exceed 12 mm. Outwardly, they look like flat plaques; their surface may be uneven and their shape may be irregular. They rise slightly above the surface of the skin and are unevenly colored in brown shades. Sometimes such structures do not contain melanin.

On histological examination, the formation looks like a complex or mixed pigmented nevus, but there are signs of infiltrative growth, that is, penetration into the surrounding layers of the skin. The shape of the cells also changes: they become angular, with uneven contours, with brightly colored (hyperchrome) nuclei. The condition that allows melanoma to be excluded is the absence of penetrating (infiltrative) growth towards the upper layer of the skin - the epidermis.

VK moles can appear at any age and on any part of the body. Sometimes their number exceeds several dozen. If there are already such cases in the family, the probability of such a nevus appearing over the age of 59 years exceeds 50%. In this case, the disease is transmitted in an autosomal dominant manner. In this case, they talk about FAMMM syndrome (Family atypical multiple mole melanoma syndrome). This is the main factor in the development of skin cancer.

If a dysplastic nevus occurs in isolation, without a hereditary predisposition, then it has a benign course.

Juvenile melanoma;
Dysplastic nevus

Pigmented nevus of the conjunctiva

This formation is practically not dangerous. It can be located on the conjunctiva (mucous membrane) and is then clearly visible. Also, a pigmented nevus of the eye can lie on the choroid of the eyeball and can only be detected when examining the fundus of the eye by an ophthalmologist. This spot is formed by accumulations of melanocytes and looks like an ordinary mole.

Eye nevi can be stationary (not changing) or progressive (growing). If a lesion on the choroid grows, over time it can cause a narrowing of the visual field, reduce its acuity and cause other unpleasant symptoms. Therefore, it is removed using microsurgery or laser therapy.

Treatment of nevi

Treatment of pigmented nevus is carried out in cases where the formation is melanoma-dangerous, grows rapidly or is located in an area where it is constantly injured (for example, on the chin, temples, neck, lower back). If a person has age spots, he should regularly visit a dermatologist to have them examined and monitored.

Removal of a pigmented nevus is performed using surgery or minimally invasive intervention.

Removal of a pigmented nevus surgically is carried out if there is a risk of malignancy of the formation. Excision of the spot using a scalpel is carried out within healthy tissue, after which a scar may remain.

Minimally invasive methods are more often used on open areas of the skin, when the removal of age spots is primarily for aesthetic purposes. Applied, removal using the so-called.

Prevention of malignancy

The most likely malignant degeneration of large, unevenly colored, numerous formations. You should consult a doctor if a mole begins to grow, its surface or shape changes, redness or skin itching appears around it, bleeding, peeling, or sudden hair growth on the surface.

To prevent melanoma (skin cancer), you should follow simple rules:

• Avoid skin exposure to direct sunlight from 11 a.m. to 4 p.m.;
• refuse to visit the solarium;
• prefer light clothes with long sleeves, wear wide-brimmed hats in summer.

Using sunscreen does not reduce the risk of developing melanoma.

This type of pigmented nevus is characterized by the fact that melanocytes are located in both the epidermis and dermis. Consequently, the formation is a combination of borderline and intradermal nevi. Dermoscopically, this combination most often appears as an area surrounded by a pigment network with globular structures or a homogeneously colored/hypopigmented structureless zone with single comma-shaped vessels and other signs characteristic of intradermal nevi.

Comedon-like structures may be detected. It is believed that mixed nevus is a stage in the gradual evolution of border nevus into intradermal nevus.

When describing pigmented nevi, one cannot ignore the dysplastic nevus (Clark's nevus). This type of nevi, first described by Wallace N. Clark, Jr. in 1978, is often considered as an independent variant of benign melanocytic formations. Taking into account the fact that melanocytic dysplasia can only be confirmed by pathohistological examination and is not found in all formations suspected of it, the use of the term “dysplastic nevus” is not entirely justified. It is more correct to call these nevi Clark's nevi.

Particular attention to them is due to high risk of their malignant transformation, especially in patients with a family history of melanoma. To a greater extent, the diagnosis of Clark's nevus is clinical, and the presence of such a nevus is indicated in cases of detection of acquired, unevenly colored melanocytic formations with uneven contours, more than 4-5 mm in diameter and tending to grow. At their core, these are borderline or mixed nevi. Often the damage is multiple.

To date, there is no clear description of the dermoscopic features of Clark's nevus. Its presence can be suspected when an alternation of light and dark-colored sections of the pigment network is detected, if it is heterogeneous, if there are homogeneous zones interspersed with dots and globules against the background of the reticular pattern, etc. Often these manifestations are indistinguishable from melanoma, which greatly complicates diagnosis.

In fact, the formation turned out to be an active mixed nevus with symptoms of injury (constant friction with clothing).

An atypical pigment network on the left side of the nevus with a cluster of black dots, an abundance of globules of various shapes, sizes and colors in the central part and along the right edge. On the left there is a rather large oval zone of hypopigmentation, within which a cluster of light purple globules is visible. A similar picture may indicate the presence of melanocytic dysplasia (Clark's nevus). The formation is subject to dynamic observation or preventive excision.

1. Dermatoscopic manifestations of this pigmented nevus very diverse: a pigment network is visible on the right edge of the formation, and a pale brown globular pattern on the left. The structureless zone in the center is unevenly colored; to the left there is a cluster of small dark brown globules. The formation was regarded as a Clark nevus, and taking into account signs of clinical activity (rapid growth), it was excised. The result of pathohistological examination is a mixed pigmented nevus with signs of activity.
2. One of many similar mixed pigmented nevi on the body of a young patient. The central exophytic part of the lesion moves with the contact plate of the dermatoscope and forms a fold, which is visible in this image as a thin brown line along the left edge at the border between the pigment network and the central zone of hypopigmentation.
3. Presence of small blue-black globules and the blue and white veil, reminiscent of the structures of regression, in this case is not a cause for concern. The formation is symmetrical in all respects, the structural elements are evenly distributed in it. Diffuse white-blue coloration is caused by pressure from the contact plate of the dermatoscope and is found only within the dermal component of the nevus.
4. The left of these two nevi is a common papillomatous intradermal nevus (nevus of Unna).

Of greater interest is right-wing education. Its dermoscopic picture is unusual; it seems to be divided into two halves by a vertical line. On the left side in the center there is a globular “cobblestone” pattern surrounded by a pigment network.

On the right are very pale pink globules merging with each other, turning into an almost structureless pink area, which, closer to the edge of the tumor, is replaced by a pseudonetwork. Pinpoint vessels are visible around the entire central zone of hypopigmentation. This formation was regarded as Clark's nevus.

1. Classic example of Clark's nevus- the formation appeared at the beginning of puberty, its dimensions exceed 5 mm, there is uneven coloring and uneven contours. Dermatoscopic manifestations in the area of ​​dark-colored, eccentrically located exophytic areas suggest the presence of melanoma. In such cases, an excisional biopsy is indicated. The patient refused the operation. According to observation data over 2 years, education remains virtually unchanged.
2. In the central part of education Brown globules and a single gray-blue structure are visible on a light brown background. The pigment network along the periphery is atypical in some areas; upon careful examination, pigment dots are found closer to the edges of the nevus. In general, the formation is quite symmetrical. In such cases, dynamic monitoring is necessary. If the resemblance to melanoma increases, an excisional biopsy is performed.
3. In this nevus, located on the lower leg, the dermoscopic picture is absolutely calm - a classic example of a mixed type pigmented nevus.
4. This education is mixed nevus with a predominance of the borderline component. A pigment network in a nevus with signs of atypia, but it is not this that is of greater interest, but the dark-colored structure in the lower part of the tumor. This structure appeared in a nevus after a sunburn.

Upon closer examination, it is clear that it has all the signs of a nevus

Almost every inhabitant of the Earth who does not have black skin has at least one mole, which in medicine is called nothing more than a melanocytic nevus. The word “nevus,” somewhat unusual for the Russian language, was borrowed from Latin and means the same mole or birthmark. In the course of life, for unknown reasons, new moles appear where there was previously clear skin, and old ones disappear somewhere. This scares some people, and causes inconvenience to others, especially when dark spots begin to “decorate” the forehead, nose, and cheeks. Let's try to figure out what moles, or, in scientific terms, nevi, are, what they are, where they come from, and whether it is possible to somehow influence their appearance.

What is a nevus

In the skin of humans and animals there are special cells - melanocytes, which produce a dark pigment - melanin. In animals, it affects the color and determines the color of the eyes. In humans, it is melanin that is responsible for the intensity of tanning, that is, it protects against ultraviolet and other rays harmful to the body. When the pigment is evenly distributed throughout the skin cells, it has a uniform color and tone. If suddenly - for reasons still unknown to science - an excessive amount of it accumulates in individual cells, such areas begin to stand out against the general background, that is, a birthmark or pigmented nevus appears. Melanocytic nevus is the same. Another synonym for the same concept is melanoform or noncellular nevus. The color of these formations varies from black to light brown, sometimes purple. If the birthmark is red (wine-colored), it is called a flaming nevus and is formed due to a large accumulation not of pigment, but of capillaries located too close to the surface of the skin. For example: Gorbachev, the last president of the Soviet Union, has a flaming nevus on the head and part of the forehead.

In some people, the melanocytic nevus may be flush with the skin, while in others it may protrude slightly above its surface. The photo above shows a slightly protruding pigmented nevus. In infants, such marks are almost never observed, although scientists tend to believe that they are simply too small to be noticeable. They begin to appear more clearly around the age of 9-10 years. In most cases, simple pigmented nevi behave peacefully and do not cause any problems other than cosmetic defects.

Types of birthmarks

Hairy (one or more hairs grow from a mole, usually dark in color, regardless of whether the person is blond or brunette).

Clark, Spitz,

Let's take a closer look at some of the types.

What is papillomatous intradermal melanocytic pigmented nevus?

This long and somewhat difficult to understand definition contains several concepts at once. Thus, it was already noted above that the terms “melanocytic” and “pigment” mean the accumulation of melanin pigment in the melanocytes that produce it. essentially means the location of accumulations of melanocytes in the deeper layers of the skin and externally represents a tubercle protruding above its surface. Its synonym in medicine is the expression “intradermal melanocytic nevus”. If it has and is also located on a stalk, there is a great resemblance to papilloma. Hence the name - papillomatous nevus. Such formations appear mainly on the head (hairy part), neck, face, but can also be observed on any other part of the body. Their color, in addition to flesh-colored, can be brown, brown, black, and their finely lumpy structure vaguely resembles cauliflower. In medicine you can find other names for it, for example, linear, hyperkeratotic. There are 2 forms of them - organic, when papillomatous moles are observed sporadically, and disseminated, when there are many such warty tubercles. They are often located where large blood and nerve vessels pass. If a person has such a pattern, this may indicate diseases of the central nervous system, in particular epilepsy. Although papillomatous intradermal melanocytic nevus of the skin, appearing at birth, constantly grows little by little, it is classified as a benign melanoma-free type of pigmented formations. Despite this, it certainly needs to be shown to a specialist dermatologist to find out whether it is a nevus, papilloma or melanoma. It is especially important to consult a doctor if a papillomatous mole suddenly begins to hurt, itch, or changes color. When establishing a diagnosis, the doctor conducts a visual examination and, if necessary, performs siascopy, ultrasound, and biopsy.

Complex melanocytic nevus

This definition is used when a mole, having originated in the epidermis, grows into the dermis. Outwardly, it looks a little like a wart, with a diameter not exceeding 1 cm. Like other types of nevi, complex nevi are considered benign, however, according to medical statistics, in more than 50% of cases it can degenerate into melanoma. Therefore, it is classified as a melanoma-hazardous formation. In its structure, a complex nevus can be smooth, lumpy, hairy, warty, and most often dark in color - from brown to black.

Atypical nevus

It is believed that approximately one in ten people have an atypical or dysplastic melanocytic nevus on the skin. The photo above shows what it might look like. These birthmarks received this name due to their unclear, seemingly blurred boundaries, asymmetry, size (as a rule, they exceed 6 mm), and dissimilarity from other birthmarks. Atypical nevi can be very different in color - from light beige or pink to dark brown. In medicine, there is a synonym for this pigmented formation - Clark's nevus. If you find such a strange birthmark, you should definitely consult a doctor to make sure there is no melanoma. Doctors believe that atypical nevi themselves do not pose a health hazard, but people who have them are at risk for developing skin cancer, and not necessarily at the site of the pigment spot. During life, atypical nevi, like any other, can disappear on their own, but this is not a reason to exclude a person from the risk group.

Recurrent nevus

This is the name given to pigment spots that appear at the site where a mole was removed. A recurrent nevus usually means that the mole tissue was not completely removed and a repeat operation is required.

Spitz nevus

This is another pigment formation, due to the presence of which people are at risk for melanoma. Such birthmarks appear on the skin more often in children under 10 years of age, but adults are also not immune from them. A distinctive feature of Spitz nevus is its rapid growth. So, suddenly appearing on the skin, in just a few months it can increase in diameter from a couple of millimeters to a centimeter or more. Another unpleasant feature is that it can metastasize to adjacent areas of the skin and lymph nodes. But, despite this, in most cases, Spitz nevi are considered benign and can easily be treated in a timely manner.

Nevus of Setton

Sometimes birthmarks with a white border around the edge appear on the body. They go by two names - melanocytic nevus of Setton and halo nevus. Some people have only a few such formations, while others may have many of them, mostly on the back. The white border, scientists believe, is caused by the cells in it being destroyed by cells of the immune system. Over the years, Setton's nevi may become completely discolored or disappear completely, leaving a bright spot as a memory. In the vast majority of cases, such bordered moles do not pose a danger. But scientists have found that their presence, especially in large quantities, may be associated with the presence of diseases such as vitiligo and thyroiditis, or melanoma, which has not yet manifested itself.

Becker's nevus

This birthmark in its size resembles a giant melanocytic nevus. In about a quarter of cases, such pigmentation occurs in the fetus while still in the womb. The distinctive features of Becker's nevi are:

Hair growth on them;

Pimples appearing on them;

An increase in size up to a certain point, then a cessation of growth and some lightening of the color.

Most often, such birthmarks remain with a person for life. They do not pose any danger, but their owners should still be seen by a dermatologist from time to time.

How dangerous are birthmarks?

Some people believe that moles can eventually develop into melanoma or other types of skin cancer. However, this is wrong. In the vast majority of cases, any birthmark (or melanocytic nevus) does not threaten anything. You need to worry and immediately rush to the doctor (dermatologist, oncologist) if suddenly the following changes begin to occur with the mole:

Its color has changed, no matter in which direction;

It has become asymmetrical (for example, convex on one side);

The color or structure of the rim of the birthmark has changed;

The mole began to hurt, itch, and bleed;

The size of the birthmark has increased sharply.

In all cases, if a new mole differs from existing ones, or an old one suddenly becomes somehow unusual, you need to consult a doctor as soon as possible.

What to do with moles?

If the nevi do not bother you in any way, and if they are located on safe areas of the skin, you just need to watch them. If they are located where they can often be injured (on the palms, on the feet, on the neck, on the head, on the waist) or on the face, which causes cosmetic defects, it is recommended to remove them. Such operations should be entrusted only to doctors - a surgeon, a dermatologist. Epidermal nevi are recommended to be removed only by surgery. It is performed under local anesthesia and is therefore painless. Papillomatous melanocytic nevus of the skin, especially those located on the stalk, is sometimes more appropriate to remove with liquid nitrogen. In recent years, laser treatment of moles and their excision with a radio knife have also been successfully used.

After surgery, the doctor, as a rule, sends the removed fragments for histological examination to be completely sure that there is no cancer.

It is completely unacceptable to remove nevi on your own using traditional methods. Especially often, people try to get rid of papillomatous nevi on the legs by tying them with thread. This leads to blocking the blood supply to the mole, and it may actually fall off. But in most cases, this method of “treatment” provokes the development of changes in the cells of the epidermis or dermis and leads to disastrous consequences.

A benign brown pigment formation located simultaneously in the epidermal layer of the skin and the dermis. A complex nevus looks like a round papule or wart with a diameter of up to 1 cm, rising above the skin level. Its diagnosis includes examination, dermatoscopy and siascopy, and, if necessary, ultrasound. Histology of a complex pigmented nevus is carried out after its removal. Given the likelihood of nevus transformation into melanoma, patients need to be monitored by a dermatologist. The safest and optimal methods for removing a complex pigmented nevus are the radio wave method and surgical excision.

Together with intradermal and borderline pigmented nevi, complex pigmented nevus belongs to the main types of melanocytic nevi of epidermal origin. It begins its growth in the upper layer of the skin - the epidermis, and then grows into the dermis. Thus, unlike most other moles, a complex pigmented nevus is located simultaneously in both the epidermis and dermis. This fact was the reason for its name - dermoepidermal or complex nevus.

Complex pigmented nevus is a benign skin tumor. However, according to various authors, transformation into melanoma can occur in 50-80% of cases of complex pigmented nevus. Therefore, in clinical dermatology it is classified as melanoma-hazardous and requires a certain oncological alertness.

Manifestations of complex pigmented nevus

Due to its location in both layers of the skin, a complex pigmented nevus combines the characteristics of an intraepidermal (borderline) and intradermal nevus. The epidermal component of the nevus causes its intense brown, and in some cases almost black, color. The presence of an intradermal component causes the nevus to be slightly elevated above the general level of the skin and therefore may resemble a common wart.

A complex pigmented nevus looks like a papule or a dome-shaped, round node. Its surface is often smooth, and the growth of bristly hair is noted on it. There are complex nevi with a keratinizing or warty surface. In most cases, the nevus is located on the face or scalp, but can have any location. A complex nevus rarely reaches a significant size, usually its diameter does not exceed 1 cm.

Diagnosis of complex pigmented nevus

A complex pigmented nevus is diagnosed by a dermatologist based on examination, dermatoscopy and siascopy of the pigment formation. To determine the extent of nevus growth into the dermis, ultrasound of the skin formation can be used. Suspicion of malignant degeneration of a nevus or melanoma is an indication for an urgent consultation with a dermato-oncologist.

Carrying out a biopsy of a complex nevus is dangerous due to its injury, which can lead to malignant degeneration into melanoma. For this reason, histological examination of nevus tissue is most often carried out after its complete removal. It reveals the characteristic arrangement of nests of nevus cells in both the epidermis and dermis.

Differential diagnosis of a complex pigmented nevus is carried out primarily with melanoma and other types of pigmented nevi: blue nevus, borderline pigmented nevus, Setton's nevus, Dubreuil's melanosis, as well as warts, papillomas, senile keratoma, dermatofibroma.

Treatment of complex pigmented nevus

Complex pigmented nevus requires observation by a dermatologist. The absolute indication for its treatment (removal) is regular trauma or the appearance of signs of malignancy. Nevus removal may be performed for cosmetic reasons. Methods for removing complex pigmented nevus include: laser removal, radio wave method and surgical excision. Electrocoagulation and cryodestruction are not used due to the risk of traumatizing the formation and incomplete removal, which can stimulate malignant growth.

Removal of moles with a laser is applicable in the case of a complex nevus, if it involves using a laser as a scalpel and allows subsequent histological examination of the removed formation. It is most advisable to use the radio wave method or surgical excision of a complex nevus, since they make it possible to completely remove nevus cells, which is of great importance in terms of preventing melanoma.

And we also have

Every person with light skin color has moles or nevi on their body. They can be both congenital and acquired. A melanocytic nevus is a small spot on the skin characterized by darker pigmentation.

There are several types of moles:

• intradermal;
• melanocytic;
• warty or papillomatous;
• congenital.

Melanocytic nevi are any pigmented moles on the body.

An intradermal pigmented nevus is a spot formed due to a disturbance in the production or distribution of melanin. Such spots, as a rule, appear in early childhood and remain with a person for life. The following symptoms are characteristic of intradermal or intradermal melanocytic nevus:

• color uniformity throughout life;
• absence of unpleasant sensations in the area of ​​the mole;
• clearly defined contour;
• absence of inflammatory processes in cells.

As a rule, such nevi are safe and do not transform into melanoma.

Papillomatous melanocytic nevus is one of the types of intradermal nevi. Such spots are characterized by the presence of a stalk and a lighter shade. Outwardly, they are easily confused with papilloma due to the fact that the mole looks like a growth. Typically, papillomatous intradermal melanocytic nevi are light pink in color and soft in texture. Such growths do not have a clearly defined contour and do not pose a danger, but they are often injured.

Congenital melanocytic nevi are rare. The development of such a formation on the skin begins in the prenatal period, so the child is born with a mole. A distinctive feature of such spots is that they increase in size as the child grows. Small specks do not pose a danger, unlike large ones. If the surface of the mole is heterogeneous, any changes should be carefully monitored and observed by a dermatologist.

There is also a complex skin nevus, which is a dark, convex spot. Such benign neoplasms can develop into melanoma and therefore require careful monitoring. Doctors often suggest removing such spots.

Why do moles appear?

An intradermal melanocytic nevus is a cluster of specially pigmented cells. Factors leading to the appearance of moles on the skin:

• ultraviolet radiation;
• phototherapy;
• severe skin damage;
• burns;
• some dermatological diseases;
• hormonal disorders;
• immunodeficiency.

Many people have probably noticed how new spots appear on the skin after severe sunburn. Exposure to sunlight can lead to disruption of pigment production and the formation of spots of any size.

In childhood, new moles often appear after a course of phototherapy. There is also an increase in the number of spots with atopic dermatitis in newborns.

Disturbances in skin pigmentation and the appearance of new age spots and moles are often observed after burns. Household, chemical and sunburns, accompanied by the formation of large blisters on the skin, are one of the common causes of the appearance of acquired melanocytic nevi.

Certain inflammatory processes and skin infections can also cause melanocytic spots to develop. The appearance of moles after treatment for lichen is often noted.

The formation of new moles is observed in women during periods of hormonal changes in the body. So, spots can appear on the body during puberty, pregnancy and at the onset of menopause.

The appearance of congenital melanocytic nevus is due to the peculiarities of intrauterine development of the fetus.

Which nevi are dangerous?

In most cases, melanocytic moles do not pose a health risk. Their flat shape allows them to avoid injury and damage, so the risk of cells degenerating into a malignant tumor is minimal.

Papillomatous intradermal nevus and complex convex spots require observation. The risk of developing negative consequences if such spots are damaged is quite high, so the patient is recommended to be checked annually by a dermatologist.

The following symptoms are reasons to visit a doctor:

• itching of the skin around the spot;
• inflammation of moles;
• increase in size or change in color of the spot;
• sudden bleeding;
• peeling of the skin.

If the nevus is located in areas of contact with clothing or in skin folds, you should consult your doctor about the possibility of removing it.

Mole injuries

Often moles are damaged in everyday life. This often happens with spots located in depilated areas, skin folds or on the face in men. Accidentally cutting off a nevus while shaving is one of the most common causes of damage to these benign formations.

Raised spots can be accidentally damaged in everyday life, for example, while taking a shower. Any injury can cause bleeding.

Having noticed that after damage to a mole there is bleeding, it is important to promptly carry out antiseptic treatment and stop the bleeding. To do this, the wound is treated with hydrogen peroxide, and then pressed tightly with a swab made of a sterile bandage. It should be remembered that under no circumstances should damaged nevi be allowed to become infected in order to avoid the development of negative consequences.

Removal and diagnosis of nevi

Diagnosis of nevi is carried out by a dermatologist and oncologist. A dermatologist carefully studies the features of benign formations using special equipment. If you suspect that the process of cell degeneration has begun, the doctor will recommend consulting with an oncologist.

It should be remembered that tissue scraping from moles is not carried out, as this leads to damage to the moles and is dangerous to health.

Histological analysis is carried out only after removal of the mole. The following methods are used for removal:

• surgical excision;
• radio knife;
• laser removal;
• cryodestruction.

All these methods are absolutely painless. Excision of a mole with a scalpel is performed under local anesthesia. If the mole is located on the face, it is recommended to prefer the radio wave or laser method of removal, which does not leave scars, unlike cryodestruction.

It is imperative to remove melanocytic stains that are subject to friction on clothing or are often damaged in everyday life.

Prevention measures

Despite the fact that transformation of melanocytic nevus cells is quite rare, it is important to avoid factors that injure this formation. Such negative effects include intense tanning, rubbing with clothing and accidental damage.

If nevi are located on exposed areas of the skin, it is important to use sunscreen during periods of strong solar activity.

Protecting the spots with a patch will help prevent damage to skin growths. It is important to remember that if such a benign formation on the skin causes discomfort, you should definitely consult a doctor about the possibility of removing it.