Nevus

Description:

Nevus (birthmarks) represents high-quality new growths which emergence most of researchers connects with migration in the embryonal period of melanoblasts from a neuroectodermal tube in a basal layer of epidermis. Studying of this pathology of skin is of interest because on site the inborn or acquired high-quality nevus preexisting such terrible malignant new growth as a melanoma quite often develops.

Symptoms of the Nevus:

Pigmental nevus - high-quality accumulation of pigment cells on skin. A pigmental nevus can seldom be met at babies; they begin to be shown in the childhood, and especially much they appear in youth, and with age the number of a pigmental nevus gradually decreases. The type of a pigmental nevus can be various - they can be the flat or acting over the surface of skin, smooth or covered hair. Adults need to pay attention to change of their form, color or outward as it can be one of initial symptoms of the developing malignant melanoma.

Dysplastic nevus is the pigmented spots of irregular shape and with unsharp borders, slightly rises over skin level, coloring varies them from reddish-brown to dark-brown on a pink background.

Dysplastic nevus for the first time drew attention with the unusual look and the increased frequency in some families to themselves (is descended). As a rule, a dysplastic nevus is larger than ordinary birthmarks, having 5–12 mm a diameter.

Boundary pigmental nevus. Develops in the fields of dermo-epidermal connection and it is characterized by the increased melanotsitarny activity. Clinically it has an appearance of a flat dark brown or black small knot with a diameter up to 1 cm, with a smooth dry surface more often. An important differential diagnostic character of a boundary pigmental nevus is total absence of hair on it. The boundary nevus can sometimes look a spot of roundish or wrong outlines with smooth wavy edges. The boundary nevus has no favourite localization. It can be located on face skin, necks, trunks. According to literature, a pigmental nevus on skin of a palm, soles, generative organs almost always is boundary. The boundary nevus more often is inborn, however can appear in the first years of life or even after puberty.

The blue (blue) nevus represents the small knot of dark blue or bluish color, roundish outlines which is sharply delimited from surrounding skin, a dense and elastic consistence with a smooth hairless surface. It is characterized by massive accumulations of melanin in deep layers of a derma that causes its blue color. The small knot size no more than 0,5 cm though in literature single observations of the huge blue nevus having several centimeters a diameter are described. The blue nevus more often on a face, extremities, buttocks is located. Localization in an oral cavity is possible. Glouby the nevus meets at representatives of the Asian people more often. Inborn he never is and appears preferential after puberty. Development of a melanoma on site of a blue nevus is observed seldom, but such cases are described, as induced it to carry to melanomoopasny.

Huge pigmental nevus - always inborn. It increases in sizes in process of growth of the child, reaching big size (from a palm more) and occupies sometimes the most part of a trunk, neck and other areas. Usually on a considerable extent a nevus surface hilly, warty, with deep cracks on skin. Often sites of a hypertrichosis (a hair nevus) meet. Color variirut from a nevus, grayish to black, often heterogeneous on various sites. Ozlokachestvleny a huge pigmental nevus according to various authors occurs in 1,8% to 10% of cases.

The papillomatous nevus is characterized by an uneven, hilly surface. It is often localized on a pilar part of the head, but happens also on any other site of an integument. The sizes more often big, to several centimeters, an ochertnaniye wrong, color - from color of normal skin to brownish, are more rare - dark brown or even black. It is similar fibroepitelialny the papillomatous nevus quite often is penetrated by hair.

The Vnutridermalny nevus, or ordinary birthmark, occurs practically at all people. Are located on skin and mucous membranes. This nevus inborn though can appear also during pre-natal development is more often. Pigmentation is usually brown. At the vast majority of people birthmarks are not the reason of cosmetic inconveniences.
Any pigmental new growths of skin require attention and vigilance.

Reasons of the Nevus:

The nevus (inborn or acquired) forms on skin at the expense of pigment cells – melanocytes which normal are between two layers of skin: epidermis (the most upper layer) and a derma (inside layer), and already exist there at the birth of the person.
Specific genetic features of the person are the reasons of emergence of the acquired nevus.

Treatment of the Nevus:

Their treatment consists in radical (within not changed skin) removal by method of surgical excision (stages are presented on illustrations in the bottom of the page). Use of modern atraumatic suture materials and rules of esthetic surgery allows to try to obtain hardly noticeable postoperative hems. Special vigilance should be shown to the nevus localized on injury-causing sites of skin, and also earlier injured, quickly increasing nevus, and the nevus which are intensively changing the pigmentation. All remote nevus is subject to an obligatory morphological (histologic) research.