Clinical outcomes of metachronous recurrence of gastric epithelial neoplasia based on Helicobacter pylori infection status and microsatellite stability

Abstract

Background/Aims: <i>Helicobacter pylori</i> eradication may prevent the recurrence of gastric epithelial neoplasia after endoscopic treatment. However, <i>H. pylori</i> eradication therapy is unlikely to prevent gastric cancer. This study determined the longterm results and clinical outcomes of patients with gastric epithelial neoplasia based on <i>H. pylori</i> infection status and microsatellite stability (MSS).Methods: Patients diagnosed with gastric epithelial neoplasia who underwent an endoscopic mucosal resection or submucosal dissection between 2004 and 2010 were included in this retrospective study. During the follow-up period (range, 4 to 14 years), disease recurrence was monitored, and tissue examinations were conducted for seven sets of microsatellite loci initially linked to the tumour suppressor gene locus. When <i>H. pylori</i> infection was identified, patients underwent eradication therapy.Results: The patients (n = 120) were divided into three groups: <i>H. pylori</i>-negative with MSS, <i>H. pylori</i>-positive with MSS, and microsatellite instability (MSI). After <i>H. pylori</i> eradication, the rate of metachronous recurrence was significantly different in the MSI (28.2%) and MSS groups (3.7%, <i>p</i> < 0.01). The mean duration of recurrence was 77 months (range, 24 to 139) in the MSI group. There was no recurrence after eradication therapy in patients who were positive for <i>H. pylori</i> in the MSS group.Conclusion: <i>H. pylori</i> eradication could help prevent gastric cancer recurrence in patients with stable microsatellite loci. Careful, long-term monitoring is required in patients with unstable microsatellite loci.