Skin melanosis is usually not cancerous. Melanosis is a relatively common symptom, mostly related to ultraviolet radiation, endocrine disorders, trauma, excessive friction and medication, etc. After actively removing the causative factors, melanosis can generally subside. For the long time can not subside the melanosis, can also be removed through drug treatment, brush acid treatment, laser treatment and other ways. Melanoma belongs to a kind of malignant tumor, early symptoms will also be manifested as melanin deposits on the surface of the skin, but with the progress of the disease, the melanin deposits will gradually deepen, and will continue to expand with increased hardness, pain and itching discomfort, and even cauliflower nodules or bulges will appear, rather than not only manifested as melanin deposits. Melanosis on the surface of the skin, in addition to the aesthetic impact, will not have a serious impact on the body, generally do not need to do too much treatment. If there is a sudden increase in the size and color of the melanin deposits, we recommend that you go to the hospital in a timely manner for standardized treatment under the guidance of a doctor.