Melanoma stage IV refers to the fourth stage of melanoma, where IV represents the Roman numeral for 4. Stage IV melanoma means that the melanoma is no longer confined to the local lesion but has metastasized to distant organs. The most common locations for melanoma include the skin and mucous membranes, with typical metastatic sites including the lungs, brain, liver, etc. Once diagnosed as stage IV, there are no indications for surgical treatment. Treatment primarily involves a comprehensive approach combining chemotherapy, radiotherapy, targeted therapy, and immunotherapy.