Acquired moles generally refer to pigmented moles, the causes of which include genetic factors, as well as external environmental factors such as sunlight and chemical stimulation. 1. Most of the pigmented moles appear later in life and can occur in any part of the body and at any age. The most common cause is genetic factor, and acquired environmental factors can also cause abnormal melanin metabolism, such as long-term sunlight, long-term chemical stimulation, endocrine disorders and so on. 2. Generally, pigmented nevi have no direct or indirect harm to the body, so if you do not consider the aesthetics, you can ignore them. If necessary, it can be removed by laser or cryotherapy, and surgery is needed when malignant changes are suspected. It is recommended that patients who want to remove pigmented nevus should go to regular hospitals for treatment or operation under the guidance of doctors.