A. Moles are benign tumors with very low malignancy rate Moles belong to benign tumors of the melanocyte system. Chromatophobic moles mostly occur in children or adolescence and manifest as macules, papules, warts, nodules, etc., which can occur in any part of the body. Its size ranges from a few millimeters to several centimeters, or even a large area. The color can be yellowish brown, black, or blue, purple or non-pigmented. Because black color is common, it is commonly called black nevus. In our country, the chance of malignant change of colored moles is very low. Second, be alert to moles that are prone to friction. The chance of malignant transformation of moles is very low. However, the following situations should be taken seriously: 1.Nevi usually appear between birth and 20-30 years old, and new nevi occurring at an older age should be suspected. 2. Any single mole that becomes darker or larger than other moles should raise suspicion. 3.Moles that grow on friction parts, such as palms, feet, buttocks and waist, should be removed in time due to long-term repeated external stimulation. 4. Sudden bleeding of chromatophores or the occurrence of new punctate chromatophores (satellite foci) around them should be promptly seen. 3. Malignant melanoma of skin has low incidence and high malignancy Malignant melanoma of skin is a highly malignant tumor, accounting for the third place of malignant tumors of skin. It can be produced by the malignant transformation of moles on the skin. The incidence of malignant melanoma in China is not high, about 1 in 100,000, but the death rate is high. Because patients do not know about the disease, or the onset of the disease is hidden, such as the soles of the feet, anus, perineum, etc., it is often not easy to be noticed in the early stage, and once diagnosed, it is mostly late, and the time to save is missed. 4. Clearly spot moles Whether from the perspective of beauty or from the perspective of cure, all moles should be removed, but not all moles can be removed by spotting moles, for those moles less than 1 cm in diameter and growing in non-friction parts, you can choose to spot moles. However, for those moles larger than 1 cm in diameter, if the mole is not completely spotted once, it may recur and repeated stimulation may cause melanocytic carcinoma, so surgical excision biopsy should be chosen to determine whether it is benign or malignant. Early detection, early diagnosis, early treatment There is still hope for melanoma through early treatment. There are five different periods of melanoma development, the initial stage is limited to the epidermis, there is no distant metastasis, after the expansion of excision and adjuvant treatment, about 90% of people can achieve a survival rate of more than 5 years. If treatment is abandoned, melanoma will slowly enter the vertical growth phase and invade the dermis, where there are capillaries and lymphatic vessels, and melanoma cells may invade the vessels and lymphatic vessels and cause metastasis.