Intersecting nevi are usually not malignant and the chance of malignancy is very small. If malignancy occurs, it will be several years later. A nevus is a type of nevus cell nevus, in which the nevus cells are located at the junction of the true epidermis, and the clinical manifestation is a flat papule. If a nevus becomes malignant, most of them will suddenly become larger within a short period of time or will easily break down and bleed, and will not heal easily or have conscious symptoms such as itching. In this case, it is necessary to seek medical attention promptly, and pathology is needed to confirm the diagnosis. Most of the junction nevi become malignant in the palm of the hand, the plantar area or the area where the skin is easily rubbed, such as the junction nevus on the waist may become malignant.