Nevus - a kind of formation on the skin, sometimes appearing on the mucous membranes and conjunctiva. They consist of nevus cells. People call them moles, pigment spots.
Definition and basic properties of
Non-viral cells appear during intrauterine development from the neural crest. The latter is represented by nerve nodes, cerebral membranes, melanocytes, adrenal cells.
Under the influence of various factors, nevocytes containing a large amount of melanin are formed. Cells synthesize pigment, which gives color to the skin area. The intensity of education depends on its quantity.
The pigment nevus code for ICD-10 depends on the type of formation:
- D22 - melanoform,
- Q82.5 - congenital non-tumor,
- I78.1 - non-tumor.
In childhood, nevi often remain invisible, only to adolescence due to a hormonal burst and under the influence of sunlight, they begin to make themselves felt. Sometimes there are new ones during pregnancy.
In the development of the nevus passes several stages:
- intraepithelial,
- borderline,
- intradermal.
It is interesting that in elderly people there is often a regression when nevus cells leave inside the dermis and are replaced by connective tissues.
Classification of nevi
An international classification has been developed, according to which several large groups are distinguished. Each of them has subspecies:
- epidermal-melanocytic,
- dermal-melanocytic,
- melanocytic,
- mixed and others.
Epidermal-melanocytic
This species is the most common and is found in almost all adults. It is characterized by a round or oval shape, with distinct edges. The color varies from reddish to dark brown.
Photography epidermal skin nevus
subdivided form on:
- border,
- intradermal,
- epidermal,
- complex,
- spotted,
- nevus Spitz,
- nevus Setton,
- papillomatous,
- formation of ballonobraznyh cells,
- fibroepithelial,
- intracellular,
- relapsing,
- warty,
- greasy.
Dermal-melanocytic
This type appears from melanocytes of the dermis. Single formations are rare, therefore, it is often a question of multiple character.
Is divided into:
- blue nevus( simple and cellular),
- Mongolian spot,
- nevus Ota and Ito,
- nevus Unna and Mischer,
- combined,
- deeply penetrating.
These species can have different colors, some species differ in their large sizes. They can appear on the mucous membranes.
Melanocytic
This species is one of the most dangerous. She is late diagnosed and is a prerequisite for the development of melanoma. Congenital formations are called verrux or giant nevi.
The elements themselves can be:
- papillomatous,
- papular,
- nodal.
Clark's nevus is the most disturbing, which is a frequent precursor of melanoma. Appears before puberty. New formations can appear until old age.
Mixed and other types
Mixed - transitional form of intradermal and intra-epidermal formation, which often has a spherical shape of dense consistency.
This species includes:
- vascular or anemic,( capillary hemangioma, flaming nevus, senile hemangioma, etc.),
- nevus Becker,
- dysplastic,
- papillomatous.
This photo shows what the nevus Becker looks like
There is also the white spongy nevus of Cannon affecting the oral mucosa, is a congenital disease and progresses to puberty.
Dangerous and non-hazardous species
There is one more reason for dividing all birthmarks. This is an opportunity to develop into skin cancer. Such species are melanomo-dangerous and melanomo-safe.
The first type includes:
- pigmentary borderline,
- giant congenital,
- blue,
- Dovetail melanosis,
- nevus Reed,
- nevus Spitz,
- dysplastic.
The photo shows Reed's nevus
Melanoma-safe include non-venous formations: intradermal pigmentary, fibroepithelial, verruco, Nevus "Mongolian spot", nevus Setton.
There are other educations, which in appearance look like nevi. This is hemangioma, histiocytoma, granuloma.
Species in children
These types of nevi are congenital or appear in the first months of a newborn's life. Often localized on the head in the child, face, neck, back, lip, etc.
Among the most common are:
- vascular,
- pigmented,
- pigmentless,
- comedo,
- fibromatous,
- adenomatous,
- angiomatosis,
- hyperkeratotic and others.
Causes of
There are nevi due to the influence of external and internal factors.
The cause of congenital formations is changes in embryonic development. It consists in disturbing the migration of cells that enter the skin from the neuroectodermal tube. But even this kind does not always appear in a newborn. Often his parents notice him in the first years of his life.
The acquired species do not differ in their static nature. They can change the size, color, shape, so it is necessary for them to be constantly monitored. Often the cause is endocrine surgery, as well as skin infections.
All factors affecting the formation of moles are divided into large groups:
- Local developmental defects that arise due to a violation of cell division in the late fetal development.
- Hereditary factors, when formations are encoded by a chain of genes in a DNA molecule.
- Ultraviolet radiation, leading to the stimulation of melanocytes.
- Injuries, including insect bites, scratches and wounds,
- Hormonal factors, especially in adolescents and patients with endocrine diseases.
- Viruses and bacteria that can affect the skin, like trauma.
Most birthmarks occur in people who like to spend time in a tanning salon or vacation in equatorial countries. Affect their education and factors at work.
With special care, it is necessary to monitor the skin and newly emerged formations to specialists in the chemical industry, workers interacting with carcinogens.
Clinical Symptoms
Nevuses are composed of different cells that are part of the skin. Therefore, they can have different clinical manifestations.
For example, pigmented nevuses of the skin are of light brown, red, blue or black hue. The degree of expression depends on the concentration of melanocytes. Such species evolve, change in size. They can be several millimeters or hundreds of square centimeters.
The intradermal type has clear boundaries and a soft consistency. Sometimes it has a warty shape or loses its pigmentation. This kind is manifested at the age of 10 to 30 years and never regresses.
Photo of intradermal pigment nevus
Depending on the type of formation, localization occurs at different sites. Epidermal appear more often where there are many sebaceous glands, that is, on the scalp or face.
Nevus Ota is located more often on the upper jaw or cheeks. It often spreads to the sclera and mucous membranes of the mouth.
Border nevi appear on the palms, trunk, soles. Sometimes found on the external genitalia. The color and size change is slow.
Thus, important in the differentiation of the nevus are:
- location,
- border features,
- presence of hairs growing from the formation,
- shade,
- appearance age,
- presence of progress and modifications,
- number of moles and others.
Complications of pigmented formations
The main complication is the possibility of transformation of a birthmark into a malignant tumor. Not all entities are inclined to such a change, special attention is paid to melano-dangerous formations.
Sometimes, under the influence of external factors, even seemingly harmless birthmarks can cause harm. Especially after injury or attempted self-removal.
Symptoms of rebirth:
- rapid increase in size,
- appearance of pain or pruritus,
- discoloration,
- transformation of the surface layer,
- loss of clear boundaries,
- bleeding.
Degeneration occurs at any age, but more often it is observed in 2-13% of cases. Therefore, in any case, the diagnosis and observation of specialists is required.
Diagnosis of nevus
The aim of the study was to determine whether the formation consists of benign cells or not.
A dermatologist or oncologist must conduct an anamnesis. This allows you to find out the age when the birthmark appeared, and whether changes occurred to it or not.
Visual inspection preliminarily determines the type of education. This will determine the further actions.
Hardware diagnostic methods include:
- dermatoscopy,
- biopsy,
- siascopy.
The first method is performed using a dermatoscope, which combines a magnifying glass and a camera. With the help of it a neoformation is studied in detail.
Before the procedure, a special agent is applied, increasing the transparency of the mole. This allows us to study the deep layers.
Method with an accuracy of 97% determines whether it is benign or not.
Biopsy is performed in situations where it is difficult to differentiate education. In such a situation, its excision is carried out. Often the study is conducted with an already removed mole. Trauma nevus can lead to the degeneration of education.
Syskopiya allows you to obtain a layout of the vessels, as well as the amount of collagen and melanin. The method is good for gathering information about formations located in deep layers of the skin. Using the method, melanoma is detected with 100% accuracy.
Treatment of
formations Treatment of a nevus depends on the type of education. If it is benign, then the impact on it is not advisable. It is recommended to just watch the nevus to exclude the possibility of its degeneration.
If the doctor believes that treatment is necessary, then surgery is proposed, which consists in excising the formation with the capture of healthy tissues and fat.
How to remove
- Radio wave removal allows not to damage healthy tissues. The procedure uses a radio coagulator.
- Electrocoagulation means electrocution. In this case, thermal damage occurs to the formation.
- Cryodestruction is not always indicated. The cold tissue is left in place. Gradually appears a crust that protects the damaged area from infections.
- The laser allows you to work only with the affected area and accurately direct the beam to the desired location. In this case, healthy tissues are practically not damaged.
- Surgical method is used for large or deep formations, with suspicion of oncology.
Folk remedies
Doctors do not recommend themselves to remove nevi on the body using folk remedies, since the consequences of such manipulations are unpredictable.
For the treatment, the celandine juice is applied, which is applied to the birthmark. The procedure is repeated several times a day.
Among the folk remedies are garlic juice, fig fruits, hemp oil, apple cider vinegar, honey and others.
The effectiveness of these components is not proven, to obtain a result requires a long impact, constant monitoring of the mole.
Prevention of malignancy
All nevi should be examined by a physician. Melonominoopasnye are removed immediately, which does not allow them to degenerate into an oncology. For a more accurate result, 5-10 mm of healthy tissues are captured. If necessary, plastic is performed after the procedure.
Prevention of melanoma - timely detection of precancerous forms. For this, dynamic monitoring is carried out, timely removal of such nevi.
Video about varieties of nevi: