Prevalence of H. pylori Infection and Atrophic Gastritis in a Population-based Screening with Serum Biomarker Panel (GastroPanel®) in St. Petersburg

Abstract

Background/aim: Russian Federation is among the high-incidence countries for gastric cancer (GC), with the incidence being projected to continue increasing. Using a non-invasive blood test with four stomach-specific biomarkers (pepsinogen-I (PG-I) and -II (PG-II), amidated gastrin-17 (G-17) and Helicobacter pylori (HP) IgG antibodies) in a hospital-based screening setting, we aimed to determine the prevalence of GC risk conditions: HP-infection and atrophic gastritis (AG).

Patients and methods: A population-derived cohort of 918 asymptomatic subjects (646 women and 272 men) with a mean age of 51.8 years (range=26-83) was examined with the GastroPanel® (GP) test. GP results were verified by gastroscopy and biopsies (the Updated Sydney System (USS) classification for all test-positive AG cases and for random 5% test-negatives (n=263) to correct for the verification bias.

Results: Of the 918 subjects, only 199 (21.7%) tested completely normal, while 76.7% (704/918) had HP-infection. Altogether, in 99 subjects (10.8%), GP suggested AG: atrophic gastritis in the antrum (AGA) (n=21), atrophic gastritis in the corpus (AGC) (n=69) or atrophic pangastritis (AGpan) (n=9). The overall concordance between GP and USS classification was 82.5% (217/263) with weighted kappa intra-class correlation coefficient (ICC)=0.875 (95% confidence interval (CI)=0.840-0.901). The sensitivity/specificity balance in receiver operating characteristic (ROC) analysis for PG-I as a marker of moderate/severe AGC (AGC2+) had area under the curve (AUC)=0.895 (95%CI=0.837-0.953). Using the AGC2+ end-point, verification bias-corrected specificity of PGI reached 96.4% (95%CI=94.7-97.9) and that of PGI/PGII ratio 94.6% (95%CI=92.6-96.3), with inevitable erosion in sensitivities.

Conclusion: While capable of detecting the subjects at risk for GC (HP and/or AG), GP should be the cost-effective means to break the current ominous trend in GC incidence in Russian Federation.

Keywords: GastroPanel; Helicobacter pylori; antrum; atrophic gastritis; biomarker; corpus; gastric cancer; gastrin-17; pepsinogens; population-based; risk factors; screening; verification bias.