Predictive serum biomarkers of gastric cancer and precancerous lesions

Abstract

Background: Gastric cancer is still a major health problem worldwide, despite a dramatic reduction in incidence and mortality rates. In Mongolia, gastric cancer is ranking second after liver cancer and it is increasing in the last decade. In Mongolia, gastric cancer morbidity and mortality are high, and more than 80 percent of cases are diagnosed at an advanced stage. Aim: This study aimed to evaluate PGI, PGII and gastrin-17 (G-17) levels and to determine the diagnostic performances for gastric cancer and chronic atrophic gastritis among Mongolian individuals. Materials and Methods: We enrolled a total of 114 subjects, including gastric cancer, atrophic gastritis, and healthy control, matched by age (±2) and sex. Pepsinogen I (PGI), Pepsinogen II (PGII), G-17, and H. pylori IgG levels were measured using GastroPanel ELISA kit (Biohit, Helsinki, Finland). Also, PGI to PGII ratio (PGI/II) was calculated. All statistical analyses were performed by SPSS version 26.0 (SPSS, Chicago, IL, USA). This study was performed by the Helsinki Declaration and all subjects signed informed consent to participate in this study, which was approved by the Ethics Review Committee of the Ministry of Health of Mongolia on August 24, 2018 (Approval №67). Results: Median age of the subjects was 62 (min 27, max 80), 52.6% (n=60) were male. Proportions of family history of gastric cancer and previous history of gastric disease were significantly higher in the gastric cancer group compared with atrophic gastritis and healthy control groups. The PGI, PGI/II levels was significantly decreased in gastric cancer and atrophic gastritis groups as compared to the healthy control. For atrophic gastritis, when the optimal cut-off value of PGI was ≤75.07 ng/ml, the sensitivity and specificity were 75% and 50%, respectively; when the optimal cut-off value of PGI/ II was ≤6.25, sensitivity and specificity were 85% and 44.7%, respectively. For gastric cancer, when the optimal cut-off value of PGI was ≤35.25 ng/ml, the sensitivity and specificity were 47.2% and 86.8%, respectively; when the optimal cut-off value of PGI/II was ≤5.27, sensitivity and specificity were 75% and 60.5%, respectively. Also, we developed ROC curves for combinations of biomarkers to predict gastric cancer. The AUC of PGI and/or PGI/II combination was 69.2 (95% CI 56.9-81.4, p<0.01), with sensitivity of 77.7% and specificity of 60.5%. Conclusion: PGI, PGI/II biomarkers could not be an alternative test of upper endoscopy, but might be supportive method which is identifying individuals at high risk of gastric cancer and precancerous lesions who may need upper endoscopy.