Convex birthmark. What do you need to know about it?

, medical expert
Last reviewed: 11.04.2020

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Convex birthmark (nevus) is a benign neoplasm on the skin. From the point of view of dermatologists, moles and birthmarks have similar medical causes. At the initial stage of development the mole looks like a small speck of dark color on the skin. In the future, it can remain flat or rise above the level of the skin, that is, it becomes convex. Everything depends on the location of the pigment cells. If the melanocytes are located in the epidermis (the upper layer of the skin), the mole will remain flat. The mole becomes convex when the pigment cells are located in the deep layers of the skin (dermis).


Causes of the a convex mole

A convex birthmark is formed due to pathological changes in the skin (cell proliferation, resulting in a built-up or compacting of the skin of a certain radius). Sometimes the birthmark can contain pigments of melanin, giving it a color of a darker shade. Melanin is synthesized in the presence of melanocyte cells due to exposure to ultraviolet radiation. It should be noted the role of melanotropic hormone, produced by the pituitary gland. Therefore, in the process of pigmentation of moles, not one body system is involved.

The main causes are the presence of some factors - local developmental defects, hereditary predisposition, ultraviolet radiation, hormonal failure in the body, trauma, infection and viruses.

Local causes of developmental defects

It is about birthmarks of an innate nature, which in 60% of cases are the cause of pigmented spots. In this case, a convex birthmark appears as a result of a violation of the correct division of cells during the last periods of pregnancy. In general, such a defect in the birth of a child is not noticeable. And only after 2-3 years the new formation manifests itself in a visual examination.

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Factors of heredity

At the moment, one can not exclude the occurrence of birthmarks due to hereditary pathologies of the skin. Tumor neoplasms and moles are initially encoded in certain genes in the molecule of deoxyribonucleic acid (DNA). This genetic chain is transmitted by the chromosome to the children from the parents.

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Nevuses arising from exposure to ultraviolet radiation

The growth of melanocytes in the basal layer of the skin is stimulated by ultraviolet radiation. With increased insolation, the number of melanocyte cells will increase. Thus, if you want to get a dark tint of skin (tan), resulting from the normal response of cells to the effects of sunlight, there is a danger of pathological changes in the cells of the epidermis and dermis. The appearance of such convex moles is inherent in adults, and has acquired character.

Hormonal factor

Medical observation of patients with convex birthmarks showed that hormones actively participate in the formation of nevi. According to the results of the research, it was noted that most often birthmarks of acquired character appear in adolescents during the maturation of the reproductive system of the body. Also at risk are people who have serious disruptions in the endocrine system. In rare cases, the appearance of tumors affects women during pregnancy. The main reason is the effect of hormonal adjustment of a pathological or physiological character on the functions of the pituitary gland. In these cases, the prognosis of the disease is favorable, since such birthmarks are small in size and can disappear themselves after a while.

Injuries, bacteriological infections and viruses

The traumatic factor of the formation of nevi (mechanical damage, insect bite) refers to minor and rare causes. In this case, the main role is played by the inflammatory process in various layers of the skin. As a result of inflammation, biologically active substances are formed, which stimulate the growth of cells. A similar mechanism of formation has convex birthmarks, resulting from the entry into the body of infections of viral and bacterial etiology. It should be noted that when a person is infected with the papilloma virus, the formed convex birthmark is different in nature. Therefore, from the point of view of histology and dermatology, it is classified as a papilloma, and not a nevus.

The above-mentioned factors of the appearance of convex moles allow us to determine the risk group. This includes people who are predisposed to the appearance of moles. Particular danger consists of convex birthmarks, prone to develop into malignant tumors.

Risk factors

Who can fall into the risk group:

  • people working in enterprises with increased ultraviolet radiation;
  • people associated with the chemical or other industries in the production process of which carcinogens are used;
  • people who often rest in the southern (equatorial) countries;
  • people with chronic endocrine diseases;
  • people with low immunity;
  • people with diseases whose treatment requires prolonged use of hormonal drugs;
  • people born with a large number of nevi, since this factor can lead to the appearance of new convex moles with subsequent transformation into cancer;
  • people with relatives with histological confirmation of the diagnosis of melanoma (skin cancer);

Of all the species of moles (about 50), there are usually about 10 varieties of nevi. They are subdivided into melanone-hazardous or melanopausal formations. The first type includes birthmarks without a predisposition to transformation into skin cancer. Their removal is for cosmetological purposes only. Another type of nevi is dangerous because at any time the transformation of benign cells into malignant cells can begin.

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Symptoms of the a convex mole

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Convex birthmark on the face

Usually convex birthmarks on the face do not pose a particular danger. The only factor aimed at getting rid of a nevus is a cosmetic defect. If the mole causes a feeling of discomfort, it should be removed. To date, the procedure for removing convex moles on the face is not a problem. But choose the method of removal with caution, taking into account the features of the skin of the face.

The surgical method is not suitable for aesthetic reasons, since scars may remain on the face. The method of radiosurgery is effective only when small moles are removed. Exposure to liquid nitrogen (cryodestruction) is a process that does not require large monetary costs, but takes a long time. The method of electrocoagulation carries the risk of damage to the nevus, which can lead to a malignant transformation of the mole. A safer option is the method of laser surgery. That is, none of the ways to remove convex moles on the face is 100% safe. To gain full confidence in the correctness of the choice, you need to contact a qualified surgeon for professional advice.

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Convex birthmarks on the nose

A convex mole on the nose can be considered dangerous, since it is subject to a permanent risk of mechanical damage (contact with a handkerchief, rubbing glasses, etc.). This is an unfavorable factor that acts as the starting point of the inflammation of the mole, transforming it into melanoma or skin cancer. Another risk factor is the adverse effects of ultraviolet rays. After all, no one in everyday life uses protective equipment for the nose.

Is it necessary to remove a convex birthmark on the nose? If the birthmark does not bother and aesthetically looks, then it is not necessary to delete it without fail. In those cases where the birthmark changes color, structure and shape, you need to think about getting rid of the nevus forever. Methods for removing a convex mole on the nose are the same as those on the face.

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Convex birthmark in a child

Recently, many young mothers are experiencing because of the presence of convex moles in a child. It is proved that one child of one hundred is born with moles, in the remaining cases birthmarks appear much later (approximately at the age of 5 to 6 years). The convex birthmark of a child looks the same as in an adult. Basically, these are nevuses up to 1 cm in diameter of light brown color. Often such formations do not pose a danger to the health of the child.

Another thing, if the convex mole begins to behave unusually - grows rapidly in size, changes color, bleeds or flakes. In this situation, you need to consult a specialist for advice. Also, an alarming symptom is the intensive increase in the number of moles. To date, doctors rarely insist on urgent surgical intervention. This is due to the peculiarities of the growing body. Most advised conservative treatment. But there are situations in which (for medicamental reasons) to remove the nevus is necessary urgently.

The most common method of removing a convex birthmark in a child is laser surgery. The operation itself is absolutely safe. The children bear it quite normal. It is more important to pay attention to the postoperative period. It is recommended to resort to a sparing regimen, as well as to taking medications to normalize the immune system. It is necessary to limit the child's stay in the sun, taking water procedures to the full healing of the skin. For the prevention of any complications you need to periodically take dermatological examinations. Especially it concerns the period of puberty.

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Known facts about birthmarks

  • Convex birthmarks are most often congenital.
  • Moles have the property of changing the coloration of skin pigmentation.
  • In women, nevi are formed more often (both skin and mucous membranes suffer).
  • Many do not suspect that the presence of papillomavirus, which is present in 85% of the population, is the cause of the development of convex formations similar to moles.
  • Certain types of birthmarks reach rather large sizes (more than 30cm), which reduces the quality of life of many people, causing cosmetic defects and psychological problems.
  • Especially often benign neoplasms of the skin are transformed into malignant in people who have a light tone of hair and eyes.
  • But there is also a positive fact - many people believe that people who have a large number of birthmarks are more fortunate.


Types of melanoneopausal convex moles

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Intradermal pigmentary mole

Basically, this type of nevi develops during the adolescent period. In the initial stage, it is localized in the deep layers of the dermis, not protruding beyond its boundaries. The size of the birthmark is several millimeters. The most frequent location is the skin in the throat and neck area, under the breast, in the skin folds of the armpits and groin. Over time, this convex birthmark may slightly change in shape and color.

The forecast is favorable. Malignant degeneration (malignancy) occurs in approximately 15% of cases with additional risk factors.

Papillomatous birthmark

A characteristic feature is a pronounced elevation on the surface of the skin, differing in shape and color. Visually it looks like a brownish or pink, convex birthmark with a grainy surface. When palpation is soft and painless. Usually, apart from cosmetic flaws, there is no particular concern. The place of accommodation is mainly the scalp. Very rarely it can be located on the trunk and extremities.

The forecast is favorable. The papillomatous birthmark has the property of gradually increasing throughout the life of a person, but cases of malignant transformation are very rare.

Nevus Sutton (halonevus)

In appearance it is an oval or round pale convex mole. A characteristic difference is a corolla of pale skin surrounding the base of the nevus. The preferred location is the skin of the extremities or trunk. Sometimes it can localize on the feet, mucous membranes and face. It should be borne in mind that when one birthmark of this type appears, one should look for similar ones, since single manifestations of this kind of formations are atypical.

The forecast is favorable. The neoplasms themselves disappear without treatment after a few months after the onset. Therefore, it is not recommended to delete them. Transformation of halonews into skin cancer occurs in very rare cases. Nevertheless, these birthmarks may indicate the presence of other serious diseases that should be diagnosed in a timely manner.

Types of melaneopasic convex moles

Blue nevus

Blue nevus (Jadassona-Tiche or blue) is considered a type of precancerous tumors, but, basically, refers to the type of benign formations. The name of the nevus was due to its cells, which actively produce melanin. Externally is a dark (dark blue, dark violet) or black convex birthmark. Clear statistics of the location of this new growth is not. The size of a mole in diameter does not exceed 1cm. The blue nevus is not characterized by the growth of hair on the surface. With a more thorough examination, the borders of the birthmark and the tension of the skin are noted.

The forecast is favorable. Cases when moles of this species become skin cancer are not often found. Most often this happens after unsuccessful removal or traumatization of education. However, people with blue nevus are recommended to undergo a regular and timely checkup with a dermatologist.

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Gigantic pigmentary mole

This type of nevi differs from other species in that it has an innate character, and is noticeable already in the first days of a newborn's life. External signs during examination - a large gray or brown convex birthmark. With the development of the body has a property to increase significantly (from 2 to 7cm). In some cases, it is located on large areas of the skin of the body (cheek, neck, a significant proportion of the trunk). Quite often on the bumpy surface of a convex mole, the intensity of hair growth is noted.

The forecast is favorable. Surgical treatment of this kind of moles is prescribed with the aim of eliminating the cosmetic defect. However, cases of transformation into malignant tumors are not so rare (about 10%). The reason for this phenomenon is the large size of the area of localization of moles, which increases the likelihood of their trauma.

Complications and consequences

Is a convex birthmark dangerous?

In general, the convex birthmark does not represent a particular hazard, and does not require surgical intervention. Most people live with nevi all their lives without feeling any discomfort. Moreover, at an advanced age, moles often disappear, transforming into pigmented spots. However, some types of moles are a type of precancerous diseases. This is the danger of nevi.

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Diagnostics of the a convex mole

  • Interrogation of the patient (collection of anamnesis). First of all, the family history is studied. It is specified, whether blood relatives have birthmarks and bulging birthmarks. Immediately the question of diagnosed melanoma among family members is concretized. A mandatory question is the presence of the external and internal risk factors listed above in the daily life of the patient.
  • Visual inspection data. Neoplasm is assessed according to certain criteria: the size and number of nevi, the consistency and color, the time of appearance and localization, the changes that occurred after the last physical examination.
  • Dermatoscopy. It is carried out with the help of a special medical device, which enlarges the image of the test material several dozen times. Due to this, a specialist can notice the smallest changes on the surface of a convex mole.

  • Thermometry. With the help of a special device, a local measurement of skin temperature is carried out. The study compares the temperature of healthy skin and the temperature of the surface of a convex mole.
  • Biopsy. Used at the final stage of the diagnosis, when other methods of research have already been carried out, and the diagnosis has not yet been made. An alternative to this method is the cytological analysis. It is carried out by scraping the cells of the mole. In the presence of discharge or expression on the surface of the nevus, the analysis is taken by applying the slide to the neoplasm.

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Such tests as a biochemical blood test, a general blood test and a urinalysis in a diagnostic study of convex moles are usually not prescribed. This is due to the fact that there are no characteristic changes for these neoplasms. For the purpose of studying the work of the internal organs of the patient, these tests are performed before a biopsy or before an operative procedure to remove a convex mole. In the event that moles have appeared as a result of infections or chronic diseases, the tests are repeated. This is due to the need for proper treatment, since in this case the nevus refers to the symptoms and does not pretend to have urgent treatment.


Treatment of the a convex mole

Treatment of convex moles begins after a diagnosis, including a biopsy of suspicious tissue. Drug treatment does not have an effect with already formed education, so it is practically not used. Treatment with drugs prescribed in cases where nevi formed on the background of other diseases.

Methods of treatment of convex moles:

  • removal of nevi surgically;
  • treatment with alternative means;
  • preventive measures in case of refusal of removal;

Ways to remove moles

Excision of tissues. It is carried out with the help of a conventional scalpel. It consists in removing the expanded pigment cells and a certain (about 1-2 cm) area of skin around them. The operation is performed under general or local anesthesia. The choice of anesthesia depends on the size and location of the nevus. The disadvantage of this method is the subsequent scar formation on the skin. Therefore, the method of excision of benign neoplasm tissue has recently been rarely used.

Cryodestruction. It is carried out by freezing tissues. As a result, the cells stop dividing and die. Then the frozen tissue area is removed (without damaging the skin beneath it). The advantage of this method is painlessness and the absence of scars after the procedure. But there is a disadvantage - the risk of incomplete removal, which can lead to the secondary formation of a convex mole. For this reason, cryodestruction is used to remove small moles.

Laser surgery. This is the most common method of removing convex moles. It consists in evaporation of liquid from skin tissues, which leads to cell death. Removal is carried out without the use of anesthesia (the patient during the procedure feels only heat or a slight tingling). The advantage of this method is the ability to remove multiple nevi, as well as in the subsequent absence of scars and scars. The disadvantage is the fact that it is problematic in this way to remove moles of large sizes (more than 2 cm). There is a possibility of the same consequences as after the cryodestruction.

Electrocoagulation. During this procedure, tissue cells are destroyed by the action of electric current. It is used when removing small formations.

Alternative treatment of convex moles

  • Lubricate the birthmark with honey several times a day.
  • Continuously (several times a day) lubricate the nevus with onion juice (onions).
  • Carefully rub in the mole castor oil.
  • In 100 ml of apple cider vinegar add 5 drops of ether lemon oil. To rub the birthmark with the ready-made mixture 2 times a day (morning and evening).
  • Sour apple sour on a fine grater and mix with honey (in a proportion 1: 1). Finish the gruel to lubricate the mole, tightly tie and cover with cellophane. Leave the bandage on all night. Carry out the procedure for three days.

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Herbal Treatment

  • Grind fresh milkweed. Kashitsu attach to a convex mole, tie up and leave for 2 hours. The procedure is repeated several times (until the birthmark disappears).
  • Dig out the dandelion root, rinse it thoroughly and chop it into a gruel. The resulting mixture is applied to the mole in the form of a compress for several hours.
  • Juice celandine mixed with petroleum jelly. Apply a thin layer on the surface of the mole several times a day.

It is necessary to know that the listed alternative means help only in 10% of cases. Now it is more expedient to apply to a specialist for receiving timely qualified assistance.


  1. Avoid direct exposure to sunlight.
  2. Use a cream to moisturize the skin in order to avoid increased dryness of the skin.
  3. In time, contact the dermatologist if there are unpleasant symptoms (itching, redness, peeling, etc.).
  4. Prevention of mechanical damage. If the convex birthmark is localized in the neck, palms, and feet and is constantly endangered by injury, it is better to remove it.
  5. Regularly consult a dermatologist or oncologist, and also undergo the necessary examination (at least once a year).

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A convex birthmark does not pose a particular danger to a person, so the prognosis is favorable. But we must remember that it is very important not to miss the moment of nevus degeneration in melanoma. To avoid this, it is necessary to carry out all the preventive measures listed above.

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