Update version of the Japanese Guidelines for Gastric Cancer Screening.

BACKGROUND: Although the incidence and mortality of gastric cancer have gradually decreased, its burden remains in East Asian countries. Gastric cancer screening has been performed in Japan since 1983, and the introduction of new screening techniques has been eagerly anticipated.
OBJECTIVE: To promote evidence-based screening, the Japanese guidelines for gastric cancer screening have been revised based on the new studies.
METHODS: The guidelines for gastric cancer screening have been developed according to a previously established method. To assess evidence regarding the effectiveness of the screening methods, a systematic review was conducted based on an analytic framework including clinical questions aiming at reducing mortality from gastric cancer. The following methods were assessed for gastric cancer screening: upper gastrointestinal series (radiographic screening), gastrointestinal endoscopy (endoscopic screening), Helicobacter pylori antibody test and serum pepsinogen tests. Based on the balance of the benefits and harms of each screening method, recommendations for population-based and opportunistic screenings were formulated.
FINDINGS: After the Japanese guidelines for gastric cancer screening were published in 2005, several observational studies on radiographic and endoscopic screenings have been reported. Three case-control studies have evaluated mortality reduction from gastric cancer by endoscopic screening. Notably, evidence of the H. pylori antibody and serum pepsinogen tests was insufficient. Although false-positive results, false-negative results, and complications were observed in endoscopic and radiographic screenings, the complication rates were higher in endoscopic screening than in radiographic screening. Overdiagnosis was not estimated directly in both methods. RECOMMENDATIONS: Radiographic and endoscopic screenings for gastric cancer are recommended for population-based and opportunistic screenings. The H. pylori antibody and serum pepsinogen tests are not recommended for population-based screening because of insufficient evidence.