Does Helicobacter pylori in the gastric stump increase the cancer risk after certain reconstruction types?

Background: In the intact stomach, Helicobacter pylori associated gastritis is considered to be a risk factor for cancer. After partial gastrectomy increased mucosal cell proliferation associated with chronic bile reflux has been claimed to increase the risk for cancer in the gastric stump, whereas the influence of H. pylori infection is not so clear. Material and methods: The study was a retrospective study with 130 patients, who had undergone partial gastrectomy for peptic ulcer. The cell proliferation rate was determined from immunohistochemical stainings of gastroscopy biopsies with Ki-67 antibodies from gastric remnants. Results: The mean labelling index (LI) was 30.8%. There was no clear association between H. pylori infection and proliferation rate. A significant difference in proliferation rate was seen between patients with a reconstruction type known to be associated with bile reflux and those with a reconstruction without bile reflux. The difference was small in H. pylori negative patients but strong in those with bile reflux and H. pylori infection. The LI increased with age. Smoking had no significant effect on proliferation whereas use of NSAIDS seemed to inhibit proliferation. Conclusions: Ki-67 is a convenient method for assessing the proliferation rate of the gastric epithelium. Bile reflux and H. pylori infection seem to have a synergistic effect on cell proliferation in the gastric remnant and may explain the increased risk of cancer after partial gastrectomy.