Related articles: Atypical snows
Definition
An atypical nevus is a small pigmented lesion, flat (macula) or in relief (papula), characterized by a disordered architecture of the melanocytes.
Generally, a benign melanocytic nevus has a regular and symmetrical shape, sharp edges, a homogeneous color and a diameter of less than 5 mm. The atypical nevi, on the other hand, are characterized by larger dimensions (diameter greater than 6 mm) and variable color with different shades from brown to brown; in addition, the margins are irregular and / or appear to fade towards the surrounding skin. Sometimes, a red peripheral halo is present.
Unlike many melanomas, however, atypical nevi are predominantly roundish and have a minor chromatic irregularity.
Atypical nevi often arise on photoexposed skin areas, but they can also appear in generally covered parts of the body, such as buttocks, breast and scalp.
Multiple injuries increase the risk of developing a malignant skin tumor, especially if there are more than 50 atypical nevi and melanoma familiarity. Therefore, these patients should avoid excessive exposure to the sun, undergo specific checks at least once a year and perform a regular self-examination to check for any changes in the snow.
Possible Causes * of atypical Snows
- Albinism
- Melanoma
- Spitz nevus
