Every day, a large number of people come to the hospital for consultation or treatment for mole removal. Among this group of people, there are those who are too ugly for cosmetic purposes and those who are superstitious and believe that it affects their fate. The true cause of a mole evolving into a malignant melanoma is still unclear, and trauma or various external stimuli (such as chronic friction) are often considered as triggers. However, if the following five types of “sudden changes” are found, it should be taken seriously and early medical attention should be sought: 1) sudden increase in size; 2) darkening; 3) surface erosion, ulceration, bleeding or swelling; 4) self-induced pain or itching; 5) satellite lesions appearing around the mole. What kind of moles need attention and early removal? Generally speaking, pigmented moles that grow on the palms of the hands, soles of the feet, genitals, under the nails, fingers, toes and mucous membranes should be treated with extra caution. From external features alone, pigmented moles with a diameter of 5 mm or more, varying shades of color distribution, very irregular shape and uneven surface must be treated with caution. In order to avoid turning into malignant melanoma, the following kinds of moles should be removed as early as possible: 1. Moles on mucous membranes: such as moles on the oral mucosa, conjunctiva, vagina, and the part of the foreskin that is turned out. 2. Moles stimulated by long-term friction: such as moles growing in the bra and waist of pants. 3.Moles on the limbs: Because moles in this area have a higher chance of becoming malignant melanoma than those in other places. Although most of us have moles on our body, the probability of cancer is very small, so we don’t need to be overly panic, and moles that don’t grow on friction parts instead can’t be removed easily, and sometimes if they are not removed cleanly, they will grow again and stimulate the malignant change of moles instead. It is not uncommon for some young people to die as a result of blindly removing moles. If you go to an unqualified beauty salon and use laser, freezing or potion to get rid of them, they are often not complete but stimulate the malignant proliferation of melanocytes, and the chance of malignant change will be tens of times higher than the original one. It is better to go to regular medical institutions for mole spotting.