Combined FIT, H. pylori testing not linked with lower gastric cancer mortality
Inviting patients to get both Helicobacter pylori stool antigen testing and a fecal immunochemical test (FIT) was associated with lower gastric cancer incidence than FIT alone after adjustment, but no change in related mortality, according to a Taiwanese trial.
An invitation to a Helicobacter pylori stool antigen (HPSA) test combined with a fecal immunochemical test (FIT) did not reduce rates of gastric cancer or gastric cancer mortality compared with an invitation for FIT alone, a randomized trial in Taiwan found.
To determine if adding an HPSA test to FIT affected rates of gastric cancer, researchers randomized 63,508 residents of a county in Taiwan to an invitation to HPSA testing plus FIT and 88,995 to an invitation to FIT alone. Screening participation rates were 49.6% for HPSA plus FIT and 35.7% for FIT alone. Average participant age was 58.1 years, and 46.8% were female. Median follow-up for individuals who got HPSA plus FIT was 5.7 years, compared with 5.4 years in individuals who underwent FIT alone. Testing occurred between January 2014 and September 2018, and final follow-up was in December 2020. Findings were published by JAMA on Sept. 30.
Incidence rates of gastric cancer were 0.032% in the HPSA plus FIT group and 0.037% in the FIT-alone group (mean difference, −0.005% [95% CI, −0.013% to 0.003%]; P=0.23). Gastric cancer mortality rates were 0.015% in the combined group and 0.013% in the FIT group (mean difference, 0.002% [95% CI, −0.004% to 0.007%]; P=0.57). A total of 12,142 participants had positive HPSA results, and of these 8,664 received antibiotic treatment, with eradication occurring in 91.9%. In analyses adjusted for differences in screening participation, length of follow-up, and patient characteristics, an invitation for HPSA plus FIT was associated with lower rates of gastric cancer (relative risk [RR], 0.79 [95% CI, 0.63 to 0.98]) but not with gastric cancer mortality (RR, 1.02 [95% CI, 0.73 to 1.40]) compared with FIT alone. Researchers noted participants in the HPSA plus FIT group had more gastric cancer risk factors than those in the FIT-only group.
Limitations include that many randomized individuals were unreachable to invite and not every participant who received an invitation for screening underwent testing. Although the study did not show an effect on mortality from the intervention, it “highlighted several advantages of combining FIT with H pylori screening,” the researchers concluded.
An accompanying editorial noted that the inclusion of an HPSA test did increase participation in an organized screening program for colorectal cancer by 13.9%. “This innovative trial conveys valuable insights for the primary prevention of gastric cancer, with potential application to diverse settings. Notably, the results show that implementation of H pylori test-and-treat strategies is indeed possible using screening platforms already in place,” the editorialists wrote.