Everyone has moles, but not everyone knows that moles can become cancerous. Did you know that moles can become cancerous? The so-called cancerous moles are also known as melanoma. Melanoma is a malignant tumor that originates from melanocytes in pigmented areas of the skin, mucous membranes, eyes and central nervous system. Generally, moles on human body are not dangerous. There is no need to remove them if they are not for cosmetic reasons, but it cannot be ruled out that a seemingly harmless mole may one day become cancerous. When a mole becomes diseased, its development period is long. Unlike tumors in the body, melanoma originates from the surface and is visible. Skin changes can be detected by careful observation of all parts of the body. How do moles become cancerous and how can we know if a mole is cancerous? Observe the moles on your body carefully and pay attention to the details. 1.Normal moles are neither painful nor itchy, if a black mole suddenly appears itchy then it is time to be cautious. 2.We all know that common moles are very small, most of them are smaller than the tip of a blunt pencil, which is normal. On the contrary, if it is larger than the blunt pencil tip or suddenly grows, it is recommended to go to the hospital immediately to remove it. 3. Pay attention to the neatness of the shape of the mole. A normal mole has a regular shape and smooth surface. If inflammation or redness in the edge area is found, it is recommended to go to the hospital for examination as soon as possible. 4. Whether the color of the mole is pure or not is especially important. Either light brown or black, with a single color, is normal. On the contrary, the danger of mixing two colors is approaching. For those who are worried about the malignant change of their body moles, they can go to regular hospitals for dermoscopy. Dermoscopy is a non-invasive diagnostic tool that can assess the specific subsurface morphological structure and can very accurately identify whether the nevus on your body is a benign pigmented nevus or a malignant melanoma, minimizing the risk of missed melanoma diagnosis. Prevent melanoma and reduce direct sunlight. We all know that the sun’s rays are strongest and most toxic between 10 a.m. and 3 p.m. People with light skin and many dark moles should be aware that frequent presence during this time can especially increase the chances of developing melanoma. In summer, you should wear a hat, sunglasses, an umbrella and sunscreen. Try to walk in the shade of trees or buildings when you go out. When traveling, do your homework beforehand and bring sunscreen and sun protection tools. Especially for older people, don’t think it’s okay to have a tan. It’s not a matter of being pretty, it’s a matter of being healthy. Prevent melanoma and reduce mole friction. Experts say that special care should be taken for moles that are prone to frictional areas. For example, the bottom of the foot is the place where the human body is subjected to force, as well as the waist of pants, neckline, the part where you wear a bra, etc. Long-term friction can lead to malignant changes, and preventive removal is recommended if possible. To prevent melanoma, strengthen the body. Strengthening physical fitness is one of the most important means to prevent diseases, including melanoma and other malignant tumors. Daily exercises such as walking, swimming, yoga, Tai Chi, etc. are recommended. Each person can choose the exercise that suits him/her according to what he/she needs.