Role of nitrites in the genesis of adenocarcinoma associated with Barrett's esophagus.

BACKGROUND: Barrett's esophagus (BE) is one of the complications of gastroesophageal reflux disease (GERD) and a premalignant condition. It consists of a process of replacement of the squamous epithelium of the esophagus by intestinal columnar epithelium containing goblet cells, known as specialized intestinal metaplasia with goblet cells, and several factors have been related to its pathogenesis. The objective of this study was to evaluate an experimental model of duodenogastroesophageal reflux and the effect of ingestion of sodium nitrite solution on the genesis of adenocarcinoma associated with Barrett's esophagus.

MATERIALS AND METHODS: Sixty male Wistar rats were divided into four groups. Twenty were not submitted to surgery and served as controls (10 animals ingesting only water and 10 ingesting water plus a solution of sodium nitrite), while the remaining 40 animals were submitted to side-to-side duodenogastroesophageal anastomosis (20 animals ingesting only water and 20 ingesting water plus the sodium nitrite solution). The Vienna classification for dysplasia and adenocarcinoma was used in the analysis of results.

RESULTS: After 42 weeks of observation, Barrett's esophagus was found in 26.3% (5/19) of the animals submitted to surgery that had not ingested nitrites compared to 72.3% (13/18) of the animals in the group submitted to surgery and given nitrites. Six cases of adenocarcinoma (33.3%) were also found in this latter group. Barrett's esophagus was not found in any of the animals that were not submitted to surgery. Categories 2, 3 and 5 of the Vienna classification were only found in the animals submitted to surgery that also received sodium nitrite (66.7%).

CONCLUSION: The ingestion of sodium nitrite associated with duodenogastroesophageal reflux plays an important role in the genesis of adenocarcinoma associated with Barrett's esophagus.