Current issues and future perspectives of gastric cancer screening

Abstract

Gastric cancer remains the second leading cause of cancer death worldwide. About half of the incidence of gastric cancer is observed in East Asian countries, which show a higher mortality than other countries. The effectiveness of 3 new gastric cancer screening techniques, namely, upper gastrointestinal endoscopy, serological testing, and "screen and treat" method were extensively reviewed. Moreover, the phases of development for cancer screening were analyzed on the basis of the biomarker development road map. Several observational studies have reported the effectiveness of endoscopic screening in reducing mortality from gastric cancer. On the other hand, serologic testing has mainly been used for targeting the high-risk group for gastric cancer. To date, the effectiveness of new techniques for gastric cancer screening has remained limited. However, endoscopic screening is presently in the last trial phase of development before their introduction to population-based screening. To effectively introduce new techniques for gastric cancer screening in a community, incidence and mortality reduction from gastric cancer must be initially and thoroughly evaluated by conducting reliable studies. In addition to effectiveness evaluation, the balance of benefits and harms must be carefully assessed before introducing these new techniques for population-based screening.

Keywords: Gastric cancer screening; Helicobacter pylori antibody; Mortality; Serum pepsinogen test; Upper gastrointestinal X-ray; Upper gastrointestinal endoscopy.

Figure 1

Meta-analysis of 3 studies predicting gastric cancer risk. Meta-analysis was conducted on the base of the results of previous studies using the random effect model by Stats Direct3 (Stats Direct Ltd. Cheshire United Kingdom). Subjective studies are shown in Table 3. Although there is no cancer in group A in the Wakayama study by Ohata et al[38], it assumed that three was 1 cancer in group A in this study for meta-analysis. Because of the small number of group D, groups C and D were combined. The relative risk of group B was calculated and referred to that of group A. The relative risk of group C + D were calculated and referred to those of group A and group B.