A renal neoplasia was observed in a slaughtered 33 month old neutered Piedmontese male cattle. The neoplastic tissue was characterized by lardaceous features, and fibrotic tissue was evident with boundless interlacing, which separated the lesion in distinct diffusely irregular lobules. The lungs showed several macroscopical subpleuric nodules. Histological investigations showed multiform and distinct features of renal tumour. Anaplastic and embryonal aspects were represented by poorly differentiated or undifferentiated cells. Rarely, neoplastic epithelial elements were organized in pseudo-tubular formations. Immunohisto- chemical staining for detection of cytokeratins, vimentin, actin, S100, desmin and factor VIII was performed. Ultrastructural findings revealed two different populations of epithelial cells. Histological, immunohistochemical and ultrastructural findings in the lungs confirmed the diagnostic hypothesis of a metastatic tumour from the kidney.

Key words: Bovine, Histology, Immunohistochemistry, Nephroblastoma, Transmission electron microscopy