Pancreatic tissue (original and recut sections) from Fischer 344 rats fed 2,6-dichloro-p-phenylenediamine in a chronic (2-year) carcinogenesis bioassay was evaluated for presence of pancreatic hepatocytes (PH) by light microscopy. PH were found in dose groups as follows: males–0 ppm (controls)–0/50 (0%), 1,000 ppm–4/50 (8%), 2,000 ppm–9/50 (18%); females-0 ppm (controls)–1/50 (2%), 2,000 ppm–15/50 (30%), 6,000 ppm–15/49 (31%). This represented a significant dose-related increased incidence of PH in 2,000-ppm males, and 2,000- and 6,000-ppm females. A statistically significant increase (p < 0.01) in pancreatic acinar atrophy and fibrosis was also seen in treated female rats, but the relationship of these lesions to the PH is unclear.
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