Nephroblastoma with Mucus-Producing and Argentaffin Cells in a Pig

Nephroblastoma is the most common primary renal neoplasm of swine and man. this report describes a swine nephroblastoma localized at the caudal pole of the left kidney, extending to the renal hilum which, on light microscopy, showed unusual mucus-producing epithelial cells of many tubules. the presence of intracytoplasmic mucin was confirmed by pas-diastase positivity and alcianophilia both at ph 2.5 and at 1.0. mucin-producing cells revealed cytokeratin 19 and pankeratin ae1/ae3 positivity, and some of them a chromogranin a immunohistochemical positivity; they were also positive for grimelius stain. in veterinary medicine, even if the occurrence of mucus-producing cells in nephroblastoma has rarely been observed, this is the first description of a case of swine nephroblastoma with mucus-producing cells positive for neuroendocrine markers, thus a neuroendocrine origin was suspected.