Background: To examine the effect of anastomosis on experimental carcinogenesis in the colon of rats.
Methods: Forty-three 10-week-old male and female Sprague-Dawley rats were operated on by performing an end-to-side ileorectostomy. Group A:16 rats received no treatment. Group B: 27 rats received 18 subcutaneous injections weekly at a dose of 21 mg/kg wt of 1-2 dimethylhydrazine (DMH), from the eighth day after the intervention. Animals were sacrificed between 25-27 weeks. The number of tumours, their localization, size and microscopic characteristics were recorded. A paired chi-squared analysis was performed comparing tumoral induction in the perianastomotic zone with the rest of colon with faeces.
Results: No tumours appeared in the dimethylhydrazine-free group. The percentage tumoral area was greater in the perianastomotic zone compared to tumours which had developed in the rest of colon with faeces (p = 0.014).
Conclusion: We found a cocarcinogenic effect due to the creation of an anastomosis, when using an experimental model of colonic carcinogenesis induced by DMH in rats.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2518563 | PMC |
| http://dx.doi.org/10.1186/1471-2407-8-217 | DOI Listing |
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