Giant abdominal osteosarcoma causing intestinal obstruction treated with resection and adjuvant chemotherapy

Figure 3 The tumor. A: The tumor consisted of atypical spindle or polyhedral cells that were intimately associated to neoplastic bone deposited in a lacy pattern (haematoxylin and eosin stain, original magnification × 20); B: The tumor cells were mitotically active and frequently demonstrated atypical mitotic figures (haematoxylin and eosin stain, original magnification × 40).