If it is not an eyesore, you can actually ignore it. However, if it suddenly becomes bigger, its color is significantly deeper than before, its surface is elevated, and it is itchy or painful, easily broken and bleeding, then you should be careful, these may be signs of cancer! Everyone has moles of all sizes, but only a small percentage of them are cancerous. You should pay attention to the following situations: 1) a mole suddenly becomes bigger, its color is significantly deeper than before, its surface is raised and itchy or painful, and it is easy to break and bleed; 2) the pigment on the surface of a mole is unevenly distributed, and irregular pigment halo or hypopigmentation appears around it; 3) small black dots or satellite-like damage appears on the skin around a mole, etc. If you find the above abnormalities, you should rush to the dermatology department of the hospital to remove the suspicious moles and do pathological examination to confirm whether they are cancerous or not. In addition, the following moles, regardless of whether they have changed or not, should be removed as soon as possible to prevent cancer 1. moles that grow on parts that are often subject to friction (such as at the beard, perineum and bra); 2. pigmented moles that grow on some special parts, such as under the feet, palms and finger (toe) nails; 3. moles that are larger than 5 mm in diameter; 4. moles that repeatedly become infected. Former U.S. President George Bush Jr. once knocked off several spots on his face to prevent pigmented moles from becoming malignant. Of course, the sudden darkening or enlargement of a mole is not absolutely an indication of cancer, especially when this change occurs during pregnancy, there is no need to panic, because at this time the color of the mole will be darker than before and has a tendency to increase. However, you should be more careful and it is better to consult your doctor at a dermatologist.