Risk assessment in relatives of gastric cancer patients: hyperproliferation, genetics, and Helicobacter pylori infection

Gastric cancer remains one of the most lethal human cancers. A family cancer history should always be included in the evaluation of cancer patients. Hereditary cancer should be excluded, especially in young patients with diffuse gastric cancer. Current recommendations of the European Helicobacter pylori Study Group include offering H. pylori testing and eradication to first-degree relatives of gastric cancer patients. Approximately 10% of cases of gastric cancer present with some kind of familial aggregation, but only 1–3% of gastric carcinomas arise as a result of clearly defined genetic syndromes that require genetic counselling and aggressive preventative measures. In the remaining families, no specific abnormalities, either genetic, biochemical or histological, responsible for the increased risk have been identified. However, several lines of evidence suggest that the increased cancer risk in first-degree relatives of gastric cancer probands is mostly dependent on Helicobacter pylori infection clustering.