Malignant melanoma (referred to as malignant black) is a highly malignant tumor, mostly occurring in the skin, accounting for the third place of skin malignant tumors (6.8%-20%). The incidence rate in the world and China has been increasing in recent years, and the number of malignant melanoma in our department in the past 10 years has increased 10 times compared with the previous 10 years, which has both the trust of patients to the Department of Dermatology of Shenyang Military General Hospital and the increase of patients, as well as the factor of increasing incidence of the disease. This disease can save lives if treated with early and timely surgery, but late treatment is often not easy to control the development of the disease, so it deserves attention. Clinical manifestations Malignant melanoma occurs in adults and elderly people over 30 years of age, with few cases in young people and rare cases in children. According to statistics, only 4.2% of children under 12 years of age have the disease. The youngest patient found in our department is 19 years old, with an earlier age of onset. The early manifestation is the appearance of black damage on normal skin, or the recent enlargement of an existing melanocytic nevus with deepening pigmentation. As the lesion increases in size, it may be raised in the form of a plaque or nodule, or may be myxoid or cauliflower-shaped, with a surface that breaks down and bleeds easily. It may be surrounded by an irregular halo of pigmentation or a halo of depigmentation. If it grows to the subcutaneous tissue, it will appear as subcutaneous nodules or masses. If it spreads to the surrounding area, satellite lesions may also appear. The majority of patients have a single primary lesion, but there are cases in which only metastases are seen and no primary lesion can be found, mostly in the lower extremities, especially the foot and plantar areas. The primary foci are mostly found in the lower extremities, especially in the foot and plantar area. The disease is associated with race and genetics, trauma and irritation, sunlight and immunity. Malignant transformation of nevus cell nevus is indicated by: (1) significant and rapid enlargement of nevus cell nevus; (2) deepening of color and redness; (3) formation of surface crusts; (4) frequent bleeding from the affected area; (5) itching, pain, and rupture; (6) enlargement of nearby lymph nodes; and (7) occurrence of satellite damage around the area. It is important to note that nevus cell nevus (mostly junctional nevus or blue nevus) in areas of frequent friction and pressure such as hands and feet (especially) should be observed regularly, especially for those who often do foot massage or have habitual scratching of the lesions, so that abnormalities can be detected and treated early. Differential diagnosis Namely, nevus cell nevus, blue nevus, juvenile melanoma, etc. Treatment The malignancy of malignant nevus is high, metastasis mostly occurs, and the prognosis is more serious. Therefore, early diagnosis and timely and reasonable treatment are very important. 1.Surgical treatment: Early malignant nevus is excised or biopsied, and the depth should include subcutaneous tissue. Excise 5~8 cm of normal skin around the tumor and try to avoid amputation. 2.Local lymph node dissection: it has a certain role in preventing metastasis. 3.Chemotherapy: suitable for advanced patients with metastasis, but the long-term effects are disappointing. 4.Immunotherapy: has a certain role. 5.Radiotherapy: it can reduce the compression symptoms caused by visceral metastases. In conclusion, the current treatment effect of malignant black is still generally unsatisfactory. Patients with stage I-II take more thorough surgical resection and strive to achieve cure; patients with stage III-IV metastases use comprehensive therapy in order to achieve remission, prolong survival time and reduce patient pain. In recent years, with medical progress, the 5-year cure rate of malignant melanoma patients seen in our department has exceeded 75%, and those with more than 5 years exceeded 70. Therefore, we should not be overly afraid of this disease, but actively prevent it, treat it early, and adhere to consolidation therapy at a later stage, most patients have the hope of complete cure.