SUMMARY: Aim : To investigate the effect of the eradication of Helicobacter pylori on histological gastritis.Methods : Twenty‐six patients with moderate to severe atrophy received successful eradication therapy of H.pylori. Four patients dropped out and 22 were followed up prospectively for 5 years. The grades of gastritis were estimated from gastric biopsy specimens. The grade of intestinal metaplasia was also evaluated by dye‐endoscopy using methylene blue (methylthioninium chloride). The serum levels of pepsinogen, gastrin and anti‐parietal cell antibody were also determined.Results : The grades of atrophy decreased in patients with successful eradication therapy in the gastric corpus (before vs. 5 years after eradication, 2.09 ± 0.15 vs. 0.91 ± 0.17; P < 0.01) and in the antrum (2.14 ± 0.17 vs. 1.36 ± 0.17; P < 0.01). The levels of intestinal metaplasia were also decreased in the corpus (0.91 ± 0.24 vs. 0.50 ± 0.16; P < 0.05) and in the antrum (1.41 ± 0.20 vs. 1.00 ± 0.16; P < 0.05), which was also demonstrated by the methylene blue (methylthioninium chloride) staining method (33.4 ± 8.2% vs. 23.0 ± 6.5%; P < 0.05). The improvement of corpus atrophy correlated well with the high serum level of pepsinogen I (P = 0.005), but showed no correlation with the levels of anti‐parietal cell antibody.Conclusions : These results suggest that gastric atrophy and intestinal metaplasia are reversible events in some patients.

Summary: Background : It is controversial as to whether the development of gastric cancer is influenced by Helicobacter pylori eradication. If eradication itself influences the tumour morphology, this may affect the tumour discovery rate.Aim : To investigate the morphological changes in the gastric neoplasm after H. pylori eradication.Methods : We studied 37 patients with eradication therapy. After a 1‐month follow‐up, endoscopic re‐evaluation was performed and the appearance was compared with first image. All lesions were resected endoscopically, and were subjected to histological assessment and to immunohistochemistry. Serum gastrin levels were determined before and after eradication.Results : Twenty‐nine of 37 patients underwent successful eradication. The appearance of 11 lesions (33% of 33 lesions) became indistinct after successful eradication. All lesions were of the superficial‐elevated type and the height of the lesions decreased. We detected normal columnar epithelium over the neoplasm in eight of the lesions. Higher expression of single‐stranded deoxyribonucleic acid in the deep area was characteristic in tumours with an indistinct appearance. These changes did not correlate with the serum gastrin levels.Conclusions : The morphology of the gastric neoplasm change after eradication in the short‐term. This may contribute to the decreased tumour discovery rate.

The grade of gastric mucosa atrophy caused by Helicobacter pylori (H. pylori) infection is closely associated with the risk of gastric cancer, especially of the intestinal type. Interobserver and intraobserver agreement for endoscopic gastric mucosa atrophy in subjects with H. pylori-uninfected, currently infected and past infected was investigated. Endoscopic images of 91 patients, 34 images per patient, were assessed. The assessors were 4 endoscopist groups: Japanese and Vietnamese experienced (≥7, ≤ 15 year experience with endoscopy) and Japanese and Vietnamese beginner (≤ 3 year experience) groups. Each group comprised 3 endoscopists. The grades of atrophy were classified as 3: none to mild (C-0 and C-1), moderate (C-2 and C-3), and severe (O-1, O-2, and O-3) using the Kimura-Takemoto Classification. After a period of 2 weeks, images of all patients were reevaluated by the investigators. Interobserver and intraobserver agreement was calculated by kappa statistics. The kappa values for the interobserver agreement in the groups of Japanese and Vietnamese experienced, and Japanese and Vietnamese beginner were 0.474, 0.408, 0.291, and 0.373, respectively. The kappa value of intraobsever agreement in the Japanese and Vietnamese experienced endoscoists ranged from 0.585 to 0.871. On the other hand, the value in the beginner endoscopists ranged wider than that in experienced endoscopists, from 0.264 to 0.866. Our results indicated that, although intraobserver agreement for gastric mucosa atrophy was good to excellent, interobserver agreement was moderate in experienced endoscopists. This suggests that better guidelines and firm criteria may be needed to properly diagnose and grade gastric atrophy.