Abstract: A 50-year-old male patient was admitted to hospital due to scalp papules with pruritus for 3 months, which worsened accompanied by erosion and exudation for 2 months. The initial lesion presented as soybean-sized red papules with itching, which ruptured and exuded fluid after scratching. Histopathology revealed proliferation of irregular vascular lumens in the dermis with obvious atypical endothelial cells and visible mitotic figures. Immunohistochemistry showed positive expression of vascular endothelial markers CD31, CD34, ERG and Fli-1, negative HHV-8, and Ki-67 positive (approximately 10%). Combined with PET-CT findings indicating liver, bone and multiple lymph node metastases, the patient was diagnosed with stage IV scalp angiosarcoma. From June to November 2025, the patient received chemotherapy with tislelizumab combined with liposomal doxorubicin plus ifosfamide. The lesions gradually shrank and bleeding exudation ceased. Follow-up till May 2026 showed that the lesions basically subsided without newly developed metastases.

Key words: angiosarcoma, scalp, immunotherapy combined with chemotherapy, misdiagnosis, metastasis