恶性纤维组织细胞瘤为一种罕见病,多误诊为不典型纤维黄色瘤或上皮样肉瘤。患者男,67岁。因左大腿内侧结节3月,进行性增大1月就诊。皮损组织病理检查示:肿瘤中成分呈多形性表现,部分细胞似成纤维细胞样交织排列呈漩涡状;有些细胞似组织细胞样,可见形状怪异的多核巨细胞。免疫组化:Vim(+)、CD163(+)、CD68(+)、CD34血管(+)、Ki-67 index 30%。 Malignant fibrous histiocytoma is a rare disease, misdiagnosed as atypical fibroxanthoma or epithelioid sarcoma. Patient male, 67 years old. Due to the left thigh medial nodules in March, progressive increase in January treatment. Histopathological examination showed that the tumor showed pleomorphic components, some cells like fibroblast-like intertwined swirling; some cells like cell-like, showing the shape of weird multinucleated giant cells. Immunohistochemistry: Vim (+), CD163 (+), CD68 (+), CD34 vessels (+), Ki-67 index 30%.