Association of Helicobacter pylori-dependent gastritis with gastric carcinomas in young Japanese patients: histopathological comparison of diffuse and intestinal type cancer cases

Aims: The causal relationship of H. pylori gastric colonization with gastri c cancer development has not as yet been fully elucidated. The prevalence o f H. pylori infection increases with age in the asymptomatic population in Japan, and reaches a high plateau in those older than 40 years. The objecti ve of this study was to assess the link between H. pylori and gastric carci nomas in patients younger than 40 years. Methods and results: Detection of H. pylori and assessment of background mu cosa based on the Sydney system was performed histopathologically for 40 Ja panese gastric cancer cases younger than 40 years and compared with 40 age- and sex-matched controls. H. pylori infection in gastric mucosa was detect ed significantly more frequently (P < 0.001) in patients with cancer (29/40 ; 72.5%) than in controls (11/40; 27.5%). Additionally, by histopathologica l comparison between intestinal (18 cases) and diffuse (70 cases) types of young gastric cancer patients, mucosal atrophy and intestinal metaplasia we re found to coexist with acute and chronic inflammation in the background m ucosa of both intestinal and diffuse types, being significantly more preval ent than in young controls. Conclusions: A well as the high prevalence of H. pylori in young subjects w ith gastric cancer, it is clear that persistent infection induces mucosal d amage, resulting in atrophy and intestinal metaplasia. Thus, acute/chronic gastritis could play an essential role in the early development of neoplasi a in the stomach.