骨肉瘤为起源于原始间叶细胞的最常见的原发性恶性骨肿瘤 ,发病率占骨肿瘤的 35 .1% [13] 。原始间叶细胞是一种分化很低具有多向分化潜能的细胞 ,能分化成多种结缔组织细胞、平滑肌细胞、内皮细胞。因此骨肉瘤细胞具有明显的多向性 ,骨肉瘤的组织学结构具有多样性 ,组织学类型 Osteosarcoma is the most common primary malignant bone tumor originating from the primitive mesenchymal cells, accounting for 35.1% of the bone tumors [13]. The primitive mesenchymal cells are cells with very low differentiation and multi-directional differentiation potential and can differentiate into a variety of connective tissue cells, smooth muscle cells, and endothelial cells. Therefore, osteosarcoma cells have obvious pleiotropy. The histological structure of osteosarcoma has a diversity of histological types.