Are the nitrites and nitrates responsible for the carcinoma in the operated stomach?

ABSTRACT

The carcinogenesis of the operated stomach has been attributed to several etiologies: bilio-pancreatic reflux, achlorhydria, hypochlorydria, atrophic gastritis, atypical bacteria, food and environmental factors, nitrites, nitrates, N-nitroso compounds, the two different types of epitelium in the suture line and other. Seventy two male WISTAR rats (300-380 g) were employed, divided into 2 groups and observed during 8 months, drinking water only or aqueous solution of potassium nitrite plus potassium nitrate (30 mg/kg/day). Each group was subdivided into other 4 groups with 9 animals, submitted to gastrotomy (GT) (control group), gastrojejunostomy plus truncal vagotomy (GJ + TV), BILLROTH II gastrectomy plus truncal vagotomy (BII + TV) and Roux-en-Y gastrectomy plus truncal vagotomy (RY + TV). After the observation period, the animals were sacrificed and performed histopathological studies of the operated stomachs. The results showed that the animals that ingested nitrite + nitrate solutions presented significative findings of cystic gladular hyperplasia (41,5 per cent), dysplasia (19,6 per cent) and carcinoma (5,6 per cent). Carcinomas were found in the animals submitted to GJ + TV and BII + TV. The authors concluded that the ingestion of nitrite and nitrate causes important modifications into the mucosa of the gastric stump, however more studies are needed to clarify the mechanisms of carcinogenesis in the operated stomach.