A nevus is a pigmented nevus. It is a benign neoplasm composed of nevus cells, also known as nevus cell nevus, cellular nevus, melanocytic nevus, and nevus. It is common and can occur in almost everyone, from infancy to old age, and increases in number with age, often increasing significantly during pubertal development.
Females tend to have more moles than males, and whites have more moles than blacks. Occasionally, they are seen on mucosal surfaces. There are various types of clinical manifestations. The color is mostly dark brown or inky black, and a few colorless moles have no color.
What does a nevus look like?
The basic damage is usually macules, papules, nodules, warts or papillae <6mm in diameter, mostly round, often symmetrically distributed, well-defined, with regular margins and uniform color. The number of nevi varies from single, several or even dozens, and some damages may have one to tree roots with short and thick black hairs. Due to the different pigment content of nevus cells, they may appear brown, brown, blue-black, black or normal skin color, yellowish, or dark red clinically. Sun exposure can increase the number of pigmented nevi in exposed areas.
Classification of nevus
According to the distribution of nevus cells, they are divided into junctional nevus, intradermal nevus and mixed nevus.
1.Junctional nevus
They are usually small, 1-6 mm in diameter, smooth, hairless, flat or slightly above the skin surface, and light to dark brown in color. It can occur on any part of the body.
2.Mixed nevus
Similar in appearance to junctional nevus, but may be higher, sometimes with hair penetration, mostly seen in children and adolescents.
3.Intradermal nevus
They are common in adults and appear as hemispherical raised papules or nodules with a diameter of several millimeters to several centimeters, with a smooth or papillary surface, or with a tip, and may contain hair. Intradermal nevi usually do not increase in size. They are mostly found on the head and neck.
Pigmented nevi are unstable and often undergo a growth and evolution process from maturation to aging. Most of the nevi are small and flat at the beginning, and later they develop into mixed nevi and finally into intradermal nevi.
When a junctional nevus becomes malignant, there is often mild local pain. Burning and stinging, satellite dots appear at the edge, and if it suddenly increases in size, deepens in color, has inflammatory reaction, breaks down or bleeds, we should be alert.
Precautions for moles.
Reduce friction and external factors to damage the mole. Except for cosmetic needs, treatment is usually not required.
Pigmented nevi occurring in friction-prone areas such as palmoplantar, waistline, armpit, groin and shoulder should be closely observed, especially some damages with irregular edges, uneven color and diameter ≥1.5c cm should be paid more attention. Once rapid expansion or partial elevation or rupture and bleeding are found, they should be removed promptly.
For larger lesions, surgical excision followed by skin implantation; for smaller and superficial lesions, carbon dioxide laser treatment can be given to treat the drug thoroughly, otherwise residual mole cells are prone to recurrence.
What kind of moles are recommended to be removed?
1. Moles that are prone to friction, such as palms, soles of feet, collar areas, etc. Especially, moles on the hands and feet should be closely observed.
2.Moles on mucous membrane areas.
3.Moles next to and under the nail.
4.Moles with the following changes: sudden increase in size, darkening of color, ulceration on the surface, new moles appearing around them, etc.