Primary dedifferentiated chondrosarcoma of the lung with a 4-year history of breast cancer: A case report

Figure 2 Histopathologic and immunohistochemical observation of the right hilum mass. A and B: Dedifferentiated chondrosarcoma under low magnification and medium magnification, respectively, showed the tumors characterized by the following two distinct histopathologic components: a low-grade chondrosarcoma region sharply juxtaposed with a high-grade noncartilaginous sarcoma component; C: Typical low-grade chondrosarcoma region; D: Typical high-grade dedifferentiated sarcoma region; E: Negative expression of epithelial marker Cytokeratin in dedifferentiated chondrosarcoma (DDCS); F: Positive expression of mesenchymal marker Vimentin in DDCS; G: Positive expression of S-100 in low-grade chondrosarcoma region; H: Expression of h-Caldesmon in high-grade dedifferentiated sarcoma region, suggesting that the dedifferentiated sarcoma may have smooth muscle cell differentiation (A to D: Hematoxylin and eosin staining, A: × 40, B: × 100, C and D: × 400; E to H: Immunohistochemical staining, × 100).