Background: The risk of metachronous gastric cancer is high in Japanese with esophageal squamous cell carcinoma (SCC), especially in alcoholic men, suggesting a common background underlying the gastric and esophageal cancers.
Methods: Endoscopic follow-up ranging from 7 to 160 months (median, 47 months) after the initial diagnosis was performed in 99 Japanese gastric-cancer-free alcoholic men (56.8 +/- 6.4 years) with esophageal SCC detected by an endoscopic screening examination. Chronic atrophic gastritis (CAG) assessed by the serum pepsinogen test and Helicobacter pylori status was compared between 90 of the 99 esophageal SCC cases and 180 age-matched Japanese gastric- and esophageal-cancer-free alcoholic men.
Results: The serum pepsinogen test showed a higher seroprevalence of severe CAG among the cases than among the age-matched controls (35.4% vs. 14.2% for H. pylori-seropositive, 71.4% vs. 7.7% for H. pylori-indeterminate, and 17.1% vs. 9.8% for H. pylori-negative, respectively; H. pylori status-adjusted p = 0.0008), whereas their H. pylori status was similar. The accelerated progression of severe CAG observed in the Japanese alcoholic men with esophageal SCC suggests the existence of common mechanisms by which both esophageal SCC and H. pylori-related severe CAG develop in this population. Metachronous gastric adenocarcinoma was diagnosed in 11 of the 99 gastric-cancer-free patients, and the cumulative rate of metachronous gastric cancer within 5 years was estimated to be 15% according to the Kaplan-Meier method. The age-adjusted hazard ratios were 7.87 (95% confidence interval: 1.43 to 43.46) and 4.84 (1.16 to 20.21), respectively, in the patients with severe CAG in comparison with those without CAG and those without severe CAG. Inactive heterozygous aldehyde dehydrogenase-2, a very strong risk factor for esophageal SCC in the alcoholics, was not associated with an increased risk of metachronous gastric cancer.
Conclusions: Accelerated development of severe CAG at least partially explained the very high frequency of development of metachronous gastric cancer in this population.