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Pigmented nevus can be small and giant

What it represents is a congenital pigmented.
As a rule, congenital nevi are benign melanocytic tumors that consist of nebesnyh cells.
There are such nevi in most cases because of the violation of differentiation of the bodies of melanoblast. This process occurs approximately between 10 and 25 weeks of gestation. Otherwise, if the disruption went deep, pigmented nevus may occur in the first months of a child's life. The size of these nevi may vary from tiny spots to huge dimensions. Pigmentary giant nevus is a precursor of melanoma. The conversion speed depends on the size of pigment nevus.

Compared with other nevi, pigmented nevus occurs quite often. Approximately 2% of newborns are born with this nevus. Giant nevus of the newborn occurs in one out of 500 thousand, which is fairly rare.

What is the pigmented nevus?

Pigmented nevus may appear mottled, papular, warty or nodular elements. Moreover, the color range can be anywhere from brown, to blue and even black. The surface may be with a skin pattern and lobed, bumpy, folded, papillomatous, smooth (innate deep

In size to determine the types of pigment nevus?

Precise definitions and measurements is not present, so the doctors are conventionally divided pigmented nevus into 4 groups by size:

  • Small (diameter less than 1.5 cm).
  • Average is 1.5–10 cm).
  • Larger (approximately 10-20 cm).
  • Giant (all nevi more than 20 cm).

There are multiple pigmented nevi, which are very rare (approximately 5% of all patients). Typically, multiple pigmented nevus consists of a large hearth and a small pigment spots.

Most often this type of nevus found at the bottom of the trunk, extremities, upper back and chest.

Small and medium nevi, immediately after birth can be very pale, and thus be invisible. Such nevi are growing slower than the baby, and can manifest in a few months. Therefore, as the child grows, the blur is reduced, and pigmentation increases. If it's a giant pigmented nevus, the surface may become warty and acquire the uneven color. In 95% of cases, the increase in the hair pigment newuse.

Microscopy of pigmented nevus

Most often, histological study of the structure of congenital nevi are divided into mixed epidermal, dermal types, rarely spindle-shaped cells and blue types. Almost all pigmented nevi have an increased level of melanocytes. Melanocytes are located inthe basal layer, while completely absent in the papillary layer of the dermis.

To determine the congenital nevus or not, it is enough to check nebesnyh cells in subcutaneous adipose tissue or in the lower part of the reticulate layer of derma. Another feature of congenital nevus is the detection of novozilov in the appendages of the skin.

Pigmented nevus: treatment

    • What is the risk of developing melanoma from the pigmented nevus?

      The tumor may transform into a melanoma at various recurring injuries: chemical, mechanical (peel, brush, scratch, etc.), and radiation (this includes exposure to direct sunlight and, even worse, the Solarium).

      If you are the owner of a small congenital nevus, the risk of transformation into melanoma is not more than 1-5%, which is not true of the giant newuse. The risk of melanoma development from giant pigmented nevi during lifetime can reach up to 40% !

      When to sound the alarm?

      • Seen rapid growth.
      • Started to change colour and shape.
      • Appears bleeding.
      • On newuse formed a crust or erosion.

      So that at the slightest manifestation and growth of nevus – immediately consult a doctor for treatment and removal of it. Otherwise, it can result in a poor result for you.