pigmented nevus
Fig. 6. Pigmented nevus on the skin of the neck in the form of spots, covered with hair. Fig. 7. Pigmented nevi on the skin of the back in the form papillomatosic rise on a broad basis.

Nevus (naevus) is a birthmark (pigment); characterized by the accumulation of pigment cells in various layers of the skin. Occurs in the embryonic period, childhood and adolescence, less frequently in adults and the elderly.
Epidermal nevus - brown or black smooth spot, not tend to increase and malignancy. It rarely malignities types nevus include: youth melanoma (light semi-spherical with smooth surface) and blue nevus (flat grey or black with blue shade spot).
Malignant transformation is possible in the following forms nevus: mixed, intradermal, edge (localized on the legs, palms, soles, the scrotum), the latter is most likely to malignancy.
Obligate (required malignities) is a precancerous limited melanosis. It occurs in old age, in every area of the body, including the face, mostly women. Has the appearance of brown or black unevenly colored spots with sharply defined uneven edges and warty growths with the original design of the skin.
Any nevus under the influence of one-time or repeated trauma may develop into malignant melanoma. Avoid smudging nevus cauterizing substances, cutting, bandaging thread and other traumatic manipulation, especially as in some cases the differential diagnosis between nevus and melanoma (see) is difficult. Indications for treatment nevus (surgical or radiation) are installed in the cancer establishment.
Remove progressive nevus skin of the eyelids and conjunctiva by electrocautery in the initial growth period with good results.

Fig. 1. Non-pigmented nevus interpersonalnog space age. Fig. 2 and 3. Cystic nevus in the field of a limb; Shine cavity, evolved as a result of closing the folds of the conjunctiva at their peaks. In the circle of cavities is typical for nevus the cells (Fig. 3). Fig. 4. Pigment spots iris (1) and nevus (2), slightly protruding above the surface of the iris. Fig. 5. Nevus choroid.