A classical osteogenic sarcoma of the breast: histology, immunohistochemistry and ultrastructure

A classical osteogenic sarcoma of the breast is described and the results of light microscopy, including immunohistochemistry for epithelial and mesenchymal markers, and of electron microscopy are presented. No epithelial features were detected by any of the methods used, the tumour being considered a true osteogenic sarcoma. The tumour appears to have arisen de novo, and not from a pre-existing fibroadenoma.