Spontaneous nephroblastoma is an uncommon tumor in laboratory rabbits. We recently encountered this tumor, and we describe its histological characteristics in this report. A male 3-year-old Japanese White rabbit (JW/kbs), maintained as a stock animal, suddenly showed poor condition and was found dead a few days later. At necropsy, a large mass was found that extended from one side of the renal pelvis. The cut surface of the mass was dark red in color and velvety to the touch. The kidney on the contralateral side was normal. Microscopically, the tumor mass consisted of biphasic components, which consisted of epithelial (tubular and glomerular) and blastemal (nodular) elements. No sarcomatous proliferation was observed. In addition, some of the tubules were lined by cells with a large amount of eosinophilic cytoplasm. The cells were confirmed as oncocytes by immunohistochemical and electron microscopic examinations. The present case was therefore diagnosed as a nephroblastoma with oncocytic differentiation.
A 15-year-old male cynomolgus monkey (Macaca fascicularis)
showed large bilateral masses in the maxillary sinus. In histopathological examination,
both masses revealed benign medullary lipomas within the turbinate bones. The tumors were
composed of well-developed lipocytes, trabecular bones and a few blood vessels. Although
we initially diagnosed the tumor as bilateral lipomas in the nasal turbinates, it was not
differentiated from lipomatous hamartoma. Findings, such as unique symmetrical
proliferation, lack of border from the normal marrow and the intact surrounding tissue,
indicated a lipomatous hamartoma/hamartomatous lipoma, thought to be a suitable diagnosis
of the lesion. Of most interest was that such a proliferating lesion occurred in the nasal
turbinate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.