H. Pylori May Protect Against Esophageal Cancer
Inverse relationship between H. pylori infection and adenocarcinoma reported
FRIDAY, Dec. 21 (HealthDay News) -- Despite Helicobacter pylori's well-established link with gastric cancer, a meta-analysis suggests that H. pylori infection may confer protection against Barrett's esophagus and esophageal adenocarcinoma, according to an article published in the December issue of Clinical Gastroenterology and Hepatology.
Theodoros Rokkas, M.D., and colleagues of Henry Dunant Hospital in Athens, Greece, pooled data from 18 relevant studies to investigate the relationship between H. pylori infection, and/or infection with the cagA-positive strain, and Barrett's esophagus and esophageal adenocarcinoma.
The researchers found that patients with esophageal adenocarcinoma were less likely to be infected with H. pylori (pooled odds ratio 0.52) and H. pylori cagA-positive strain (OR, 0.51). Similarly, patients with Barrett's esophagus had a reduced prevalence of H. pylori infection (OR, 0.64) and cagA -positivity (OR, 0.39). These relationships were not evident for squamous cell carcinoma of the esophagus.
"The mechanism by which H. pylori might protect against gastroesophageal reflux, Barrett's esophagus, and finally esophageal adenocarcinoma might be related to modulation of gastric acidity," write the authors. "It has been shown that corpus gastritis is associated with lower gastric output in both the basal and stimulated conditions. Furthermore, the corpus inflammation, induced by the H. pylori cagA-positive strain, accelerates the progression to multi-focal atrophic gastritis, with destruction of gastric glands, leading to further loss of gastric acidity."