Renal hyaline droplets in tumour-bearing female Wistar rats

Renal hyaline droplets were defined by histochemical and ultrastructural methods in eight female Wistar rats in a carcinogenesis bioassay. All eight rats had neoplasms of varied type (five histiocytic sarcoma, one phaeochromocytoma, one rhabdomyosarcoma, one leiomyosarcoma). Renal hyaline droplets were not seen in female rats without tumours and, although in this study, rats with tumours did not all have hyaline droplets, the source of the protein is likely to be the neoplasm. Presence of hyaline droplets may be useful as a confirmatory criterion in tumour diagnosis.