Association between Helicobacter pylori and its eradication and the development of cancer.

Background: Helicobacter pylori (H. pylori) is a gram-negative gastrointestinal pathogen that colonises the human stomach and is considered a major risk factor for gastric cancer and mucosa-associated lymphoid tissue lymphoma. Furthermore, H. pylori is a potential trigger of a wide spectrum of extragastric cancer entities, extraintestinal chronic inflammatory processes and autoimmune diseases. In the present study, we evaluated the association between H. pylori infection and its eradication with the development of subsequent gastrointestinal and non-gastrointestinal cancer.

Methods: We identified 25 317 individuals with and 25 317 matched individuals without a diagnosis of H. pylori from the Disease Analyzer database (IQVIA). A subsequent cancer diagnosis was analysed using Kaplan-Meier and conditional Cox-regression analysis as a function of H. pylori and its eradication.

Results: After 10 years of follow-up, 12.8% of the H. pylori cohort and 11.8% of the non-H. pylori cohort were diagnosed with cancer (p=0.002). Results were confirmed in regression analysis (HR: 1.11; 95% CI 1.04 to 1.18). Moreover, a non-eradicated H. pylori status (HR: 1.18; 95% CI 1.07 to 1.30) but not an eradicated H. pylori status (HR: 1.06; 95% CI 0.97 to 1.15) was associated with a subsequent diagnosis of cancer. In subgroup analyses, H. pylori eradication was negatively associated with bronchus and lung cancer (HR: 0.60; 95% CI 0.44 to 0.83).

Conclusion: Our data from a large outpatient cohort in Germany reveal a distinct association between H. pylori infection and the subsequent development of cancer. These data might help to identify patients at risk and support eradication strategies in the future.