Spontaneous incidence of oncocytic proliferative lesions in control rat kidney.
The spontaneous incidence of foci of oncocytic proliferation (oncocytic hyperplasia and oncocytoma) was assessed in a histopathological reevaluation of the kidneys of 2,391 male and female Fischer 344 (F344) groups of control rats from long-term carcinogenicity studies (involving 24 chemicals) that had been conducted by the National Toxicology Program. The overall incidence of oncocytic proliferation was 0.3%, with a male preponderance over females at 0.5% (6/1,236) versus 0.09% (1/1,155), respectively. In males, there appeared to be an association of oncocytic proliferation with advanced spontaneous chronic progressive nephropathy. Oncocytoma or oncocytic hyperplasia appear to be rare lesions in F344 rats, and observations from these carcinogenicity studies suggest that they are slow growing and tend to occur late in a rodent's life span.
['Hard|Gordon C|GC|', 'Seely|John Curtis|JC|', 'Betz|Laura J|LJ|']
D000818:Animals D015197:Carcinogenicity Tests D002273:Carcinogens D049109:Cell Proliferation D005260:Female D006965:Hyperplasia D015994:Incidence D007668:Kidney D007680:Kidney Neoplasms D008297:Male D051381:Rats D011916:Rats, Inbred F344
incidence oncocytic proliferative lesions rat kidney oncocytic hyperplasia oncocytoma