Difficult pigmentary nevus
Difficult pigmentary nevus — the good-quality pigmentary formation of brown color located at the same time in an epidermalny layer of skin and a term. The difficult nevus has an appearance of the roundish, towering over level skin of a papule or a wart with a diameter up to 1 cm. Its diagnostics includes survey, Dermoscopy and a siaskopiya, if necessary — ultrasonography. The histology of a difficult pigmentary nevus is carried out after its removal. Considering probability of transformation of a nevus in a melanoma, patients need observation of the dermatologist. The safest and optimum ways of removal of a difficult pigmentary nevus is the radio wave method and surgical excision.
Difficult pigmentary nevus
Together with an intradermalny and boundary pigmentary nevus the difficult pigmentary nevus belongs to the main types of a melanotsitarny nevus of an epidermalny origin. It begins the growth in the top layer of skin — epidermis, and then sprouts in a term. Thus, unlike the majority of other birthmarks, the difficult pigmentary nevus settles down at the same time both in epidermis, and in a term. This fact was also the cause for its name — a dermoepidermalny or difficult nevus.
The difficult pigmentary nevus is a good-quality new growth of skin. However according to different authors transformation in a melanoma can happen in 50-80% of cases of a difficult pigmentary nevus. Therefore in clinical dermatology he is classified as melanomoopasny and demands a certain onkonastorozhennost.
Manifestations of a difficult pigmentary nevus
Thanks to the arrangement in both layers of skin the difficult pigmentary nevus combines signs of a vnutriepidermalny (boundary) and vnutridermalny nevus. The Epidermalny component of a nevus causes its intensive brown, and in certain cases almost black, coloring. Existence of a vnutridermalny component promotes that the nevus is a little raised over the general level of skin and therefore can remind an ordinary wart.
The difficult pigmentary nevus has an appearance of a papule or knot of a dome-shaped, round form. Its surface more often smooth, on it is noted growth of shchetinisty hair. A difficult nevus meets an orogovevayushchy or warty surface. In most cases the nevus settles down on a face or a hairy part of the head, but can have any localization. The difficult nevus seldom reaches the considerable size, usually its diameter does not exceed 1 cm.
Diagnostics of a difficult pigmentary nevus
The difficult pigmentary nevus is diagnosed by the dermatologist on the basis of data of survey, a dermatosokopiya and siaskopiya of pigmentary education. Ultrasonography of skin education can be applied to definition of extent of germination of a nevus in a term. Suspicion on malignant regeneration of a nevus or a melanoma is the indication for urgent consultation of a dermatoonkolog.
Carrying out a biopsy of a difficult nevus is dangerous by its traumatizing which can lead to malignant regeneration in a melanoma. For this reason the histologic research of fabrics of a nevus is conducted most often after its full removal. It reveals a characteristic arrangement of nests of nevusny cages both in epidermis, and in a term.
Differential diagnostics of a difficult pigmentary nevus is carried out first of all with a melanoma and other types of a pigmentary nevus: a blue nevus, a boundary pigmentary nevus, Seton's nevus, melanozy Dyubreylya, and also with warts, papillomas, a senile keratoma, dermatofibromy.
Treatment of a difficult pigmentary nevus
The difficult pigmentary nevus demands observation of the dermatologist. The absolute indication to its treatment (removal) is the regular travmatization or emergence of signs of an ozlokachestvleniye. Removal of a nevus can be carried out for cosmetic reasons. Treat ways of removal of a difficult pigmentary nevus: removal by the laser, radio wave method and surgical excision. Electrothermic coagulation and cryodestruction are not applied because of danger of a travmatization of education and its incomplete removal that can stimulate malignant growth.
Removal of birthmarks the laser is applicable in case of a difficult nevus if it consists in use of the laser as a scalpel and allows to carry out the subsequent histologic studying of remote education. Application of a radio wave method or surgical excision of a difficult nevus as they give the chance of full removal of nevusny cages that is of great importance in respect of the prevention of a melanoma is the most expedient.