Figure 1

Histological and immunohistochemical images of canine mammary osteosarcoma. The histological sample was stained with the standard hematoxylin and eosin (H-E) method. Immunopositivity (nuclear or cytoplasmic) is shown as brown precipitate in neoplastic cells. The EnVision + System-HRP detection system was used, and the signal was visualized with chromogen 3,3-diaminobenzidine 3-3' (DAB). Arrows indicate positive nuclear staining of cells. An asterisk (*) indicates a negatively stained sarcomatous area. Images were obtained under the Olympus BX41 microscope. Original magnification: H-E (x400), Vim (x400), α-SMA (x400), Ki67 (x400), ERα (x200, x400), PR (x400), p53 (x400).