title: Helicobacter pylori and Gastric Cancer: Timing and Impact of Preventive Measures.
abstract: Helicobacter pylori (H. pylori) is a Gram negative spiraliform bacterium that is commonly found in the stomach. H. pylori infection is still one of the world's most frequent infections, present in the stomachs of approximately one-half of the world's people. H. pylori infection is etiologically linked to histologic chronic active gastritis, peptic ulcer disease, and primary B-cell gastric lymphoma (gastric MALT lymphoma) and represents the major risk factor for the development of sporadic non-cardia gastric cancer (GC) of both intestinal and diffuse type. Studies that have examined the impact of GC prevention through H. pylori eradication have shown mixed results, but recent data suggest that prevention is only efficacious in patients without intestinal metaplasia or dysplasia. This indicates that, like in Barrett's esophagus, we need better clinical risk markers to indicate which patients are at greatest risk of developing cancer to guide clinical strategies. Furthermore, recent epidemiological data have suggested a possible contribution of H. pylori in modifying the risk of developing other gastrointestinal malignancies (including esophageal, pancreatic, hepatocellular, and colorectal cancer), although mechanistically these associations remain unexplained. We review clinically relevant aspects of H. pylori infection in the context of GC development as well as studies that have examined the impact of eradication on GC development and, lastly, discuss these recent epidemiological studies connecting H. pylori infection to extragastric gastrointestinal malignancies.
authors: Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University Hospital, Magdeburg, 39120, Germany.
authors: Marino
authors: M
authors: Venerito
authors: Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University Hospital, Magdeburg, 39120, Germany.
authors: Riccardo
authors: R
authors: Vasapolli
authors: Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University Hospital, Magdeburg, 39120, Germany. daniela.deutschlaender@med.ovgu.de.
authors: Peter
authors: P
authors: Malfertheiner
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D005756:Gastritis / Q000382:microbiology / Q000473:pathology / Q000517:prevention & control; D016481:Helicobacter Infections / Q000382:microbiology* / Q000473:pathology / Q000517:prevention & control; D016480:Helicobacter pylori / Q000187:drug effects / Q000502:physiology*; D054884:Host-Pathogen Interactions / Q000187:drug effects; D006801:Humans; D007422:Intestines / Q000382:microbiology* / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000382:microbiology / Q000473:pathology / Q000517:prevention & control; D008679:Metaplasia / Q000517:prevention & control; D013274:Stomach Neoplasms / Q000382:microbiology* / Q000473:pathology / Q000517:prevention & control
chemical_list: D000900:Anti-Bacterial Agents
keywords: Eradication; Gastric cancer; Gastrointestinal malignancies; Helicobacter pylori; Intestinal metaplasia; Prevention strategies