Risk of gastric cancer in the second decade of follow-up after Helicobacter pylori eradication

Abstract

Background and aims Eradication of Helicobacter pylori reduces the risk of gastric cancer. In this study, we investigated the risk beyond 10 years after eradication of H. pylori. Methods We conducted a retrospective cohort study of 2737 patients who had yearly endoscopic follow-up after cure of H. pylori infection. For comparison of gastric cancer risk in the second decade of follow-up with that in the first decade, we calculated standardized incidence ratios (SIRs) by dividing the number of observed cases of gastric cancer in the second decade of follow-up by that of expected cases which was estimated using the incidence rate ratio of age in the first decade. Results During the follow-up for as long as 21.4 years (mean 7.1 years), gastric cancer developed in 68 patients (0.35% per year). The SIRs for diffuse-type gastric cancer was infinity (0 expected case and 4 observed cases) in patients with mild gastric mucosal atrophy and 10.9 (95% confidence interval 4.53-26.1) with moderate atrophy, whereas no significant increase of SIRs was observed in intestinal-type cancer regardless of the grade of baseline gastric atrophy or in diffuse-type cancer in patients with severe atrophy even though who had the highest risk. Conclusions The longer the follow-up, the greater the risk of developing diffuse-type gastric cancer becomes in patients with mild-to-moderate gastric atrophy at baseline. Endoscopic surveillance should be continued beyond 10 years after cure of H. pylori irrespective of the severity of gastric atrophy.

Clinicopathological Characteristics and Endoscopic Features of Early Gastric Cancers Diagnosed After Helicobacter pylori Eradication: A Retrospective Study

“…Therefore, the improvement of gastric atrophy and intestinal metaplasia was associated with a reduction in gastric cancer occurrence [18]. However, the risk of developing a diffuse-type gastric cancer increases over time in patients with mild to moderate gastric atrophy before H. pylori eradication [19]. In our study, six of 29 cases (21%) had no to mild atrophic gastritis around the EGC that occurred after H. pylori eradication.…”

“…However, few cases of EGC were detected 15 or 17 years after H. pylori eradication therapy. Endoscopic surveillance should be continued beyond 10 years after H. pylori eradication regardless of the degree of gastric mucosal atrophy [19].…”

Correct Identification of Cell of Origin May Explain Many Aspects of Cancer: The Role of Neuroendocrine Cells as Exemplified from the Stomach

“…Previously in this overview we have described the central role of the ECL cell in gastric carcinogenesis. The very slow proliferation of the ECL cell in the basal state implies that even a moderate augmentation nevertheless results in a rather slow growth taking years or decades to develop into an overt tumor [57]. A property of the ECL cells which may play a role in tumorigenesis is their production of histamine, which through its vascular effects [14] could promote cancer cell access to the blood and thus metastasis.…”

How long should patients be surveyed for gastric cancer risk after Helicobacter pylori eradication therapy? 10 years is no longer enough

“…Accordingly, H. pylori eradication therapy should be required in all patients with H. pylori infection to prevent the development of gastric cancer. As Take et al show in this issue [7], endoscopic surveillance should be continued beyond 10 years after eradication therapy for H. pylori irrespective of the severity of gastric atrophy.…”

“…In this issue of Journal of Gastroenterology [7], Take et al report a single-center retrospective cohort study of 2737 patients who received endoscopic follow-up survey after H. pylori eradication therapy for as long as 21.4 years (mean 7.1 years). Gastric cancer developed in 68 patients (0.35% per year).…”