Two cases of spontaneous malignant fibrous histiocytoma in Wistar rats.
Spontaneous malignant fibrous histiocytoma (MFH) of subcutaneous tissues was found in 2 Wistar rats of a 18-month-old male and a 21-month-old female. These tumors consisted of spindle, oval, myxoid and giant cells. In the female rat, a similar histological pattern was found in the metastatic tumor nodules in the lung and liver. In the electron microscopy, four differentiated cells of fibroblast-like, histiocyte-like, giant and undifferentiated cells were identified in these tumors. Spontaneous MFH of Wistar rats in the present study was quite similar to those reported in rats of other strains.
D000818:Animals; D005260:Female; D018219:Histiocytoma, Benign Fibrous / Q000473:pathology / Q000648:ultrastructure / Q000662:veterinary*; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains; D012376:Rodent Diseases / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology / Q000648:ultrastructure / Q000662:veterinary*