PGC-MG7 combination could be used as a follow-up panel for monitoring dynamical progression of gastric precancerous diseases

OBJECTIVE: The aim of this study was to investigate the value of the combined expression of the gastric mucosal differentiation protein pepsinogen C (PGC) and gastric cancer (GC)-associated antigen MG7 for the diagnosis of GC and prediction of the development from precancerous conditions to GC. METHODS: The gastric mucosal biopsies of 285 subjects enrolled from a region with a high incidence of GC were obtained and histopathologically examined. Subjects testing negative for GC (n=208) were followed up from 1998 to 2015. The levels of PGC and MG7 in the biopsies were determined by immunohistochemistry. RESULTS: PGC was positive in 91.4% of the non-atrophic gastritis, 26.5% of the atrophic gastritis, and 0% of the GC. MG7 was positive in 15.0% of the non-atrophic gastritis, 82.4% of the atrophic gastritis, and 94.8% of the GC. The non-atrophic gastritis group was predominantly “PGC+MG7−”. The atrophic gastritis and GC groups were predominantly “PGC−MG7+”. The rate of GC in subjects with “PGC−MG7+” staining was 113.4-fold higher [95% confidence interval (95% CI): 15.3−869.4, P<0.001] than that in subjects with other staining patterns. The sensitivity and specificity of the “PGC−MG7+” pattern were 92.2% and 78.8% for the detection of GC and 77.2% and 97.9% for GC and precancerous disease, respectively. In the follow-up cohort of non-GC subjects, the risk of developing GC was higher in those with the “PGC−MG7+” staining pattern. CONCLUSIONS: Our data suggest that the “PGC−MG7+” pattern can be employed as a useful follow-up panel for detecting individuals with a high risk of GC, and the dynamic assessment of the follow-up panel needs multi-centre large-scale validation in the future.