Synonyms
Liver spot, spider nevus, melon, skin changes Medical: Nevus
Forms and appearance of birthmarks
A distinction is made between epithelial (epithelium = uppermost layer of the skin, mucosa; epithelial = starting from the epithelium) and melanocytic (starting from the melanocytes) moles. Epithelial moles are divided into epidermal nevi and special forms. Synonyms are also hyperkeratotic nevus or nevus striatus.
First the epidermal nevus is described. This is a congenital, sharply defined thickening of the epidermis. The epidermis is the uppermost of all skin layers.
A familial accumulation is usually not observed. These nevi are common in the population and appear as soft and brownish elevations or warts. Excision, i.e. cutting out the nevi, is available as a therapy.
If the moles are disturbing, they are excised in series. In the category of epithelial nevi there are also special forms: The so-called nevus sebaceus should be mentioned here. This nevus is medium common in the population and, like the epidermal nevus, is usually congenital.
The nevus sebaceus is caused by a malformation of sebaceous glands, but also of the upper skin layers. These marks appear as circumscribed, streaky or irregular and always sharply defined, often spherical structures. Very often they are found in the scalp.
In the affected area, the hair is usually completely missing. Once puberty is complete, these nevi often recede. However, if they persist into adulthood, they should be removed, as in 15-30% of cases malignant tumors (malignancies) can develop from them.
In this case the basal cell carcinoma or spinalioma is to be considered. Furthermore, melanocytic nevi occur. This category includes epidermal melanocytic nevi and dermal melanocytic nevi.
Epidermal melanocytic nevi arise from melanocytes (pigment-forming skin cells) of the epidermis, the uppermost layer of the skin, while dermal melanocytic nevi arise from melanocytes of the dermis, the layer beneath the epidermis. Epidermal melanocytic nevi, for example, are common freckles, which are medically called ephelids. Ephelids are small, round, sharply defined, brownish spots on areas exposed to light (face, forearms).
These skin changes are permanent, i.e. always present. However, they fade in winter, but reappear when the sun shines again. They are caused by an increase in melanin.
The number of melanocytes (pigment-producing skin cells) is normal. Other times, which belong to the epidermal melanocytic nevi, are the so-called lentigines. They are similar to ephelids, but are larger and darker.
They are caused by the proliferation of melanocytes. Within this group there are different types: Café-au-lait spots are light brown and sharply defined. These spots can occur individually, but also as partial symptoms of certain diseases.
Nevus spilus is a relatively common congenital pigmentation spot. It is about 2 – 10 cm in size, sharply defined and usually light brown with small dark spots. These cracks may increase over the years.
The Becker nevus can be palm-sized. It is also well delimited and is characterized by the accompanying hair growth at the affected area. It develops mostly in young men in the 2nd decade.
About 2% of the population is affected. Dermal melanocytic nevi represent the second group of melanocytic moles. There are three different types: A nevus coeruleus is an accumulation of melanocytes in a specific layer of skin, the dermis, which is located below the epidermis.
This birthmark is acquired, has a bluish color and occurs in about 2-3% of the population. It usually appears in the form of a nodule, which has a smooth and shiny surface. Besides the congenital birthmarks, acquired forms also occur.
These liver spots are called nevuscell nevus. Here should be mentioned:
- Lentigo simplex usually occurs singly in childhood and independently of UV radiation. Multiple lentigines usually occur everywhere on the body and also UV-independently.
- Lentiges seniles are the result of chronic UV damage in areas of the body that are particularly exposed to light.
- The Mongolian stain is slightly bluish, blurred and flat.It occurs in the area of the sacrum and recedes in childhood.
Within the Mongolian race, it occurs in 90-100% of cases, while it is rare among whites.
- A nevus fusco- coeruleus occurs frequently in Mongolians and Japanese. It appears as a blue-black, flat spot. It is called Nävus Ota when it appears on the face.
In the shoulder area it is called Nävus Ito.
- The halo is easily distinguished from the other moles. It has a bright yard around the brownish nodule. Bright in this case means that the rim has no pigment.
Consequently, the edge is even lighter than normal skin. This nevus, also called sutton nevus, usually occurs in children and adolescents.
- The congenital (congenital) giant pigment nevus occurs very rarely. Mostly it comes to its formation in the lumbar and gluteal area in the context of a neurocutaneous melanosis.
This nevus is mottled brown and often accompanied by hair. Therefore it reminds of animal fur. These nevi should be removed extensively in the first week of life.
There are essentially two indications for birthmark removal.
First, the medical-diagnostic indication, if malignant skin growth is suspected. The second is the cosmetic mole removal, which is becoming more and more important and can be performed not only by dermatologists but also increasingly in cosmetic institutes. The diagnostic removal of the birthmark is medically more important and is always performed when a malignancy is suspected.
There are two different methods of birthmark removal available. One is a surgical method, which has been in use in dermatology for a long time. Here, the suspect skin area is separated from the rest of the skin by means of an incision technique and then sent to a laboratory for micro-histological determination.
There, the origin of the tissue is checked by means of microscopic and staining techniques and whether it is malignant tissue. The procedure is performed after the skin from which the birthmark has been cut out has been appropriately anesthetized. A local anesthetic is injected and the appropriate exposure time is waited for before the removal of the birthmark can begin.
After the removal of the mole, one or two stitches are usually necessary to close the incision. The procedure is generally considered low-risk. However, it is always possible that postoperative bleeding occurs and appropriate surgical measures must be taken.
In rare cases, infections may occur. Depending on the suture technique used, the scars may be larger or smaller. The intracutaneous suture technique often used today usually leads to minimal scars that are hardly noticeable from a cosmetic point of view.
Today, laser skin removal is used, especially for cosmetic birthmark removal. In this procedure, the skin pigments in the skin leading to the birthmark are destroyed. This then leads to a fading of the skin in this area.
Skin irritation can occur here, even days after the procedure. In this case, special anti-inflammatory skin creams should be applied to the skin. In both surgical procedures it is necessary to apply an appropriate protective bandage to the treated skin.
This bandage should be left on for a few days and can then be removed. Since the laser method destroys skin pigments, a histological-microscopic examination of the tissue is not possible with this procedure. There are basically two possibilities for removing a birthmark, surgical removal and laser removal.
If the birthmark is suspected of being malignant, it must always be completely removed (cut out) surgically, as this is the only way to examine the tissue histologically for malignancy. Laser treatment of birthmarks is used when the birthmark is to be removed for cosmetic reasons. The tissue is burned and can no longer be histologically examined.
With this method, the birthmark can be removed largely painlessly and without the formation of a scar. For this reason, the laser method is often used in the face or décolleté area, where a scar, just like the birthmark, would be aesthetically disturbing. The technique behind the laser is the photodynamic therapy.
The heat generated by the laser removes the birthmark superficially without creating a scar.However, the laser beam often does not penetrate deeply, which is why the laser method is not suitable for the treatment of malignant moles. The laser treatment is usually performed without local anesthesia and takes only a few minutes. The properties of the laser such as intensity, wavelength or pulse frequency can be individually adjusted. In order to prevent scarring, the sensitive lasered skin area should be protected from sunlight and infections.
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