Typical presentation: Pigmented nevi are benign neoplasms composed of nevus cells. It is common and can occur in almost everyone, from infancy to old age, increasing in number with age and often significantly more 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, with a few colorless nevi without color. The basic damage is usually macules, papules, nodules, warts or papillae <6 mm 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. What causes pigmented nevus to form? It is a developmental abnormality that occurs when melanocytes move from the neural crest to the epidermis due to an accidental abnormality, resulting in the local aggregation of melanocytes. What are the types of pigmented nevi? Pigmented nevus can be divided into three types: First, junctional nevus, located at the junction between the lower epidermis and the dermis, which is a nest of nevus cells with obvious boundaries, with a flat and smooth or slightly elevated surface and no hair. Second, intra-dermal nevus, located in the dermis, with smooth surface or wart-free elevation, dark brown color, and often with hair growth. The third is mixed nevus, which consists of junctional nevus and intradermal nevus together, slightly elevated, smooth surface, with or without hair, and darker pigment. What are the main methods of mole removal at present? It is a pity that there are several black moles on the fair skin, especially on the face, and they increase with age, so how to see how harsh. Many beauty lovers use potions to spot moles no matter what type they are, which is not correct. There are three main stream mole spotting methods: laser, surgery and drug erosion. What is laser mole spotting? The high-intensity radiation energy generated by laser can focus on the pigment particles of moles, vaporize and break them up directly, and then discharge them out of the body through lymphatic tissues, which is the most common means of mole spotting because of less trauma. What kind of moles are suitable for laser? What are the advantages and disadvantages? Most of the moles that grow on weight-bearing or friction areas such as soles, toes, palms, nail beds, neck near collar, perineum, etc. are junctional moles, and if laser treatment is used, it will cause bad stimulation to these moles, which may lead to malignant changes. In addition, laser mole removal may require several treatments, generally speaking, each treatment will not take more than 20 minutes. 3 months after the treatment, no new moles will grow in the original area, and if some melanin grows in the original area after 3 months, you need to have a second treatment at least 3 months after the first treatment. What are the pros and cons of surgical mole removal? Surgery is the biggest nemesis of moles. For moles with malignant potential, excision can also be performed at the same time as pathological examination to accurately understand the nature of the lesion, thus making the treatment more complete. For moles with a diameter of more than 0.5cm or with the possibility of malignant transformation, surgery is the best choice. However, the biggest disadvantage of surgery is that it can leave scars, which is even worse for people with scars. In addition, surgical mole removal may seem like a minor surgery, but it requires a high level of doctor's operation and the environment where the surgery is performed. Therefore, before choosing this method, please evaluate your level of scar acceptance and your own body type. Can medication erosion work? Most of the medications used for mole spotting are strong acid or alkaline medications with strong corrosiveness, which corrode the skin through the medication to make the mole necrotic and fall off, while liquid nitrogen "mole freezing" works similarly to mole spotting water, which is also "liquid nitrogen" spotted on the mole to make the skin tissue necrotic and fall off. Compared with the first two means, drug mole spotting is the most dangerous one, because the scope and depth of the drug is difficult to control, and the mole will recur when the action is shallow, and leave scars on the skin surface when the action is deep. How to prevent the malignant change of pigmented moles? For general pigmented moles, you should try to avoid stimulating them, such as rubbing and hand scratching, which will stimulate the mole cells and promote malignant changes. If physical methods such as freezing, electrocautery and laser are used repeatedly to remove pigmented moles, they do not completely eliminate the mole cells, but rather make it easier to stimulate the mole cells and make them degenerate and proliferate, which will lead to malignant changes. For those pigmented moles that occur in the armpit, palmoplantar, shoulder, groin, waist and other areas that are easily rubbed, it is best to remove them as early as possible to prevent malignant changes. How to identify moles with malignant tendency or melanoma at an early stage? The following conditions should be noticed: sudden increase in the size of the mole in the near future, uneven or deepening color; blurred border of the mole with outward infiltration or pseudopod; local itching, burning or painful sensation on the skin; redness, swelling, moisture, oozing or infection around the mole, especially at the edge; easy bleeding, crusting or shedding of the mole surface to form small ulcers; satellite black dots, black halos or nodules around the mole; mole Lymph nodes in the surrounding area are swollen for unknown reasons. Doctor's advice: Many beauty lovers use potions to spot moles no matter what type they are, which is not correct. There are many types of moles and different treatment methods are applicable to different types of moles.