While it might slightly reduce gastric cancer incidence, it does not reduce gastric cancer mortality, researchers say.
Adding an H. pylori stool antigen test to faecal immunochemical testing for colon cancer screening does not significantly reduce gastric cancer incidence or mortality compared to FIT alone, a new study shows.
The Taiwan-based randomised clinical trial involved a large sample of 152,503 individuals who were randomly assigned to one of two screening groups – FIT alone and FIT plus the H. pylori stool antigen test. The findings were published in JAMA.
“Previous studies testing whether H pylori testing or treatment could prevent gastric cancer either allocated H pylori-infected patients into antibiotic treatment and placebo groups or provided H pylori screening services without control groups,” the authors write.
“Consequently, prior to this clinical trial, to our knowledge, evidence regarding the effectiveness of a population-based screening for H. pylori was lacking.”
Gastric cancer is diagnosed in about one million people each year and causes approximately 800,000 deaths annually, they write.
“Gastric cancer is particularly common in Eastern Asia and South America, as well as in Central and Eastern Europe. Helicobacter pylori is a contributing factor to the development of gastric cancer, and bacterial eradication treatment may prevent its occurrence.
“However, whether community screening for H. pylori can reduce rates of gastric cancer or gastric cancer mortality remains unknown.”
This trial used the FIT platform of the Taiwan Colorectal Cancer Screening Program, which offered biennial single-sample FIT screening to general residents.
The program started with participants aged 50 to 69 years in 2004 and was extended to include people up to age 74 years in 2012. For this trial, the eligible age remained 50 to 69 years for both the HPSA + FIT or FIT-alone groups.
The trial found the incidence of gastric cancer was 0.032% in the group invited for both FIT and H. pylori testing, and 0.037% in the group invited for FIT alone. There was no significant difference between the two groups in terms of the number of new gastric cancer cases.
Mortality due to gastric cancer was 0.015% in the combined screening group and 0.013% in the FIT-only group. Again, no significant difference was found in gastric cancer-related deaths between the two groups.
The researchers said their study highlighted several advantages of combining FIT with H. pylori screening.
“First, by using an established infrastructure for FIT screening, H. pylori screening could be integrated into an organised screening program, for greater efficiency of care,” they write.
“Second, the referral rate for a positive HPSA result could be comparable to that of a positive FIT result.
“Third, the eradication rate of 91.9% could be high and resulted in low adverse effects associated with antibiotic treatment.”
Further studies with more controlled conditions, longer follow-up and higher participation rates may be needed to explore the issue more definitively, the researchers said.
