The Clinical Evidence Linking Helicobacter pylori to Gastric Cancer

Abstract

Gastric cancer has long been recognized to be accompanied and preceded by chronic gastritis, lasting decades. Arguably, the most important development in our understanding of gastric cancer pathogenesis over the past 50 years has been the realization that, for most cases of gastric cancer, Helicobacter pylori is the cause of the underlying gastritis. Gastritis can promote gastric carcinogenesis, typically via the Correa cascade of atrophic gastritis, intestinal metaplasia, and dysplasia. Nested case-control studies have shown that H pylori infection increases the risk of gastric cancer significantly, both of the intestinal and diffuse subtypes, and that H pylori is responsible for approximately 90% of the world’s burden of noncardia gastric cancer. Based largely on randomized studies in high gastric cancer prevalence regions in East Asia, it appears that primary and tertiary intervention to eradicate H pylori can halve the risk of gastric cancer. Some public health authorities now are starting screening and treatment programs to reduce the burden of gastric cancer in these high-risk areas. However, there is currently much less enthusiasm for initiating similar attempts in the United States. This is partially because gastric cancer is a relatively less frequent cause of cancer in the United States, and in addition there are concerns about theoretical downsides of H pylori eradication, principally because of the consistent inverse relationship noted between H pylori and esophageal adenocarcinoma. Nevertheless, establishing a link between chronic H pylori infection and gastric cancer has led to novel insights into cancer biology, the gastrointestinal microbiome, and on individual and population-based gastric cancer prevention strategies.

Gastric Cancer in the Era of Precision Medicine

“…Among clinical risk factors for GC, which include smoking, high-salt diet, high intake of meats, and bile reflux, infection with H pylori is a leading factor, especially in distal GC 18, 19, 20, 21. On the basis of improved estimates from prospective studies, 89% of new non-cardia GC cases are attributable to H pylori worldwide 22 …”

Role of Epstein Barr Virus and Gastric Carcinoma

“…Entre los factores de riesgo clínicos para el CG se incluyen: tabaquismo, dieta rica en sal, alta ingesta de carnes, reflujo biliar e infección por H. pylori [7][8][9][10] . La mayoría de los cánceres no cardiales son atribuibles al H. pylori 11 .…”

Helicobacter Pylori is the Cause of Gastric Cancer

“…Thus far, most but not all studies, systematic reviews and meta-analysis confirmed (Lin et al, 1995) that H. pylori is associated with gastric cancer. However, due to conflicting reports (Moss, 2017) in the literature regarding the relationship between H. pylori and human gastric cancer Helicobacter pylori is still not accepted as the cause of gastric cancer (Barukčić, 2005;Barukčić, 2009;Ando et al, 2006).…”