Pathology review of proliferative lesions of the exocrine pancreas in two chronic feeding studies in rats with ammonium perfluorooctanoate

Publication date: 2014 Source:Toxicology Reports, Volume 1 Author(s): Jessica M. Caverly Rae , Steven R. Frame , Gerald L. Kennedy , John L. Butenhoff , Shu-Ching Chang Two chronic dietary studies, conducted years apart, with ammonium perfluorooctanoate (APFO) in Sprague Dawley rats have been previously reported. Although both included male 300ppm dietary dose groups, only the later study, conducted in 1990–1992 by Biegel et al., reported an increase in proliferative lesions (hyperplasia and adenoma) of the acinar pancreas. An assessment of the significance of the differences between both studies requires careful consideration of: the diagnostic criteria for proliferative acinar cell lesions of the rat pancreas (for example, the diagnosis of pancreatic acinar cell hyperplasia versus adenoma is based on the two-dimensional size of the lesion rather than distinct morphological differences); the basis for those criteria in light of their relevance to biological behavior; and the potential diagnostic variability between individual pathologists for difficult-to-classify lesions. A pathology peer review of male exocrine pancreatic tissues from the earlier study, conducted in 1981–1983 by Butenhoff et al., was undertaken. This review identified an increase in acinar cell hyperplasia but not adenoma or carcinoma in the earlier study. Both studies observed a proliferative response in the acinar pancreas which was more pronounced in the study by Biegel et al. Definitive re...
Source: Toxicology Reports - Category: Toxicology Source Type: research