Melanomas are not always all black, but also brown, red, white or blue, and are asymmetrical, show variations, etc. Melanoma color distribution is uneven or has a variety of colors, may be black, brown, tan, white, gray, red, pink or blue. And it has the characteristics of asymmetrical shape and uneven margins, and may show changes such as enlargement, color or shape changes, and may also be accompanied by itching or bleeding. When melanoma is malignant, the appearance may vary greatly and the characteristics of melanoma are not quite the same in different populations. Papules, nodules, sclerosis, and ulcers may appear as the disease progresses, suggesting a poor prognosis. When melanoma appears on the skin, it is important to seek medical attention and standardized treatment.