Adenocarcinomas of the intestine induced in Syrian hamsters by N-methyl-N-nitrosourea.

The adenocarcinomas of the intestine induced in Syrian hamsters by N-methyl-N-nitrosourea (NMU) were of two histological types, superficial and intestinal. These types had distinctive characteristics regarding pattern, cytological features, secretion of mucus, and mode of growth. The histological changes induced by NMU in the mucosa of the small intestine differed from what has been described in enzootic intestinal adenocarcinoma and proliferative ileitis of Syrian hamsters. NMU produced alteration in the villous architecture and cytological change in the absorptive cells. There was marked shortening of the villi and reduced thickness of the mucosa. The villous absorptive cells were large and cuboidal with centrally placed nuclei.