Endoscopic evaluation by the Kyoto classification of gastritis combined with serum anti-Helicobacter pylori antibody testing reliably risk-stratifies subjects in a population-based gastric cancer screening program

Abstract

Background: We previously demonstrated that the Kyoto classification of gastritis was useful for judging the status of Helicobacter pylori infection in a population-based screening program, and that adding H. pylori antibody test improved its accuracy (UMIN000028629). Here, we tested whether our endoscopic diagnosis of H. pylori infection status reliably estimated gastric cancer risk in the program.

Methods: Data were collected from1345 subjects who underwent endoscopic follow-up 4 years after the end of the registration. We analyzed the association of three diagnostic methods of H. pylori infection with gastric cancer detection: (1) endoscopic diagnosis based on the Kyoto classification of gastritis; (2) serum diagnosis according to the ABC method (H. pylori antibody and pepsinogen I and II); and (3) endoscopic diagnosis together with H. pylori antibody test.

Results: During the follow-up, 19 cases of gastric cancer were detected. By Kaplan-Meier analysis, the detection rates of cancer were significantly higher in the past or current H. pylori infection groups than in the never-infected group with all 3 methods. By the Cox proportional hazards model, the hazard ratio for cancer detection was highest in evaluation with the combined endoscopic diagnosis and the antibody test (method 3; hazard ratio 22.6, 95% confidence interval 2.99-171) among the three methods (the endoscopic diagnosis (method 1); 11.3, 2.58-49.8, and the ABC method (method 2); 7.52, 2.49-22.7).

Conclusions: Endoscopic evaluation of H. pylori status with the Kyoto classification of gastritis, especially combined with serum anti-Helicobacter pylori antibody testing, reliably risk-stratified subjects in a population-based gastric cancer screening program.

Keywords: Atrophic gastritis; Cancer screening; Gastric cancer; Gastrointestinal endoscopy; Helicobacter pylori.

Fig. 1

Flowchart of subject selection. Six hundred eighty-one patients who did not met the inclusion criteria were excluded

Fig. 2

Kaplan–Meier analysis of the proportion of patients who remained free of gastric cancer. *The annual rate of detecting gastric cancer calculated by Kaplan–Meier analysis

Fig. 3

Kaplan–Meier analysis of the proportion of patients who remained free of gastric cancer according to H. pylori infection status at the time of enrollment. A Curves according to H. pylori infection status based on the endoscopic diagnosis with Kyoto classification of gastritis. B Curves according to serologically judged H. pylori infection status (the ABC method). C Curves according to combined evaluation of H. pylori infection status with the endoscopic diagnosis and serum H. pylori antibody. *The annual risk of detecting gastric cancer calculated by Kaplan–Meier analysis. †Statistical significance between curves tested by log-rank test