Patients with early gastric cancer who received treatment for Helicobacter pylori infection had a 50% lower incidence of metachronous gastric cancer, according to results of a single-center, double-blind prospective randomized clinical trial.
H. pylori therapy also improved gastric corpus atrophy grade; however, it did not impact incidence of gastric adenoma or OS.
Patients with gastric cancer typically experience advanced precancerous changes in gastric mucosa and are at high risk for metachronous development of new gastric cancer. Results from other randomized clinical trials have shown conflicting efficacy of H. pylori treatment among healthy individuals without precancerous changes and among older adults with advanced histologic changes.
Il Ju Choi, MD, PhD, of the Center for Gastric Cancer, National Cancer Center in Goyuang, South Korea, and colleagues evaluated whether H. pylori therapy may prevent metachronous cancer while decreasing histologic changes among patients with early gastric cancer.
Researchers randomly assigned 470 patients who underwent endoscopic resection of early gastric cancer or with high-grade adenoma to H. pylori eradication therapy — which included 1,000 mg amoxicillin, 500 mg clarithromycin and 10 mg rabeprazole — or placebo and 10 mg rabeprazole, twice daily for 7 days. All patients continued rabeprazole treatment for an additional 4 weeks.
Endoscopic evaluation occurred at 3 months, 6 months, 1 year and every 6 months or 1 year until each patient reached 3-year follow-up.
Metachronous gastric cancer incidence based on endoscopy at 1-year follow-up or later and improved glandular atrophy grade from baseline served as primary endpoints. Secondary endpoints included metachronous adenoma incidence and OS.
Intention-to-treat analysis included 396 patients: 194 in the H. pylori group and 202 in the placebo group.
Median follow-up was 5.9 years (interquartile range, 4-8.2; maximum, 12.9).
Fourteen patients in the H. pylori group developed metachronous gastric cancer compared with 27 patients in the placebo group (HR = 0.5; 95% CI, 0.26-0.94). Patients diagnosed with metachronous gastric cancer tended to be younger. Also, surgical treatment appeared more common among the placebo group.
Histologic analysis included a subgroup of 327 patients who underwent endoscopic biopsy at 3-year follow-up. Results of this analysis showed improved gastric atrophy grade at gastric corpus lesser curvature among 48.4% of patients in the H. pylori group compared with 15% of patients in the placebo group (OR = 5.3; 95% CI, 3.08-9.13).
Patients in the H. pylori group also showed improved intestinal metaplasia at the same site compared with the placebo group (36.6% vs. 18.3%; P < .001). However, researchers observed no significant differences in grade for either glandular atrophy or intestinal metaplasia at the antrum.
Sixteen patients in the H. pylori group and 17 in the placebo group developed metachronous gastric adenomas.
No serious adverse events occurred. Mild adverse events — which included taste alteration, diarrhea and dizziness — appeared more common among the H. pylori-treated group than the placebo group (42% vs. 10.2%; P < .001).
Limitations of the study included single-center analysis, inclusion of patients with high-grade adenoma and the use of a placebo group.
Prevention of gastric cancer can be made possible by the implementation of H. pylori screen-and-treat strategies, according to Peter Malfertheiner, MD, from Otto von Guericke University Magdeburg in Munich, Germany.
“These strategies are mandatory in populations at high risk and are established in guidelines for other persons at risk,” Malfertheiner wrote in a related editorial. “Consideration should also be given to populations with low or intermediate risk,” he wrote, adding that strategies should be used before establishment of severe gastric atrophic changes with or without intestinal metaplasia.
A noninvasive approach for prevention should be taken in combination with screening for colorectal cancer among persons aged 50 years and older in Western societies who have low or intermediate risk, Malfertheiner added. Endoscopy also can be performed among patients at risk. – by Melinda Stevens
Disclosures: Choi and the other authors report no relevant financial disclosures. Malfertheiner reports personal fees from Allergan, Biohit, and Infai outside the submitted work