Fig. 5
From: A case of primary extraskeletal osteosarcoma of the breast
The histopathological examination. The proliferation of atypical cells with oval to round nuclei and eosinophilic cytoplasm with abundant osteoid and bone formation are seen at the periphery of the tumor. The center of the tumor is composed of hypocellular fibrous maturation. Mitotic figures are frequently seen, but abnormal mitotic figures are not evident