Pigmented nevus and pigmented spots are collectively referred to as pigmented nevus and belong to localized abnormal pigmented lesions. Pigmented spots, also known as achromatous nevus, are pigmentation of tumor-free cells in the skin, such as freckles and senile spots; Unlike pigmented spots, pigmented nevus is a cell proliferation of nevus, so it is also called cell spot nevus. Pigmented spots and pigmented nevus are difficult to distinguish clinically. The nevus cells in pigmented nevus are developed from neural crest precursor cells and can produce pigment. Pigmented nevus is a benign disease, which remains stable for a long time, and the occurrence of malignant transformation is very rare. Pigmented nevus is common in face and neck skin, and occasionally in oral mucosa.

Suggestion: Most pigmented nevus do not need treatment. Facial nevus can be surgically removed when it affects the appearance. When the area is large, it can be removed by stages, or it can be transferred with free skin flap or adjacent skin flap after one-time removal. If a malignant nevus is suspected, a one-time surgical resection and biopsy should be performed; The operation should make an incision on the normal skin outside the boundary of the nevus. For example, after the excision of a small mole, you can secretly peel off the wound edge of the skin and sew it directly.