Abstract
Serum ABC classification has been attracting research attention for predicting the risk of gastric cancer. In this study, we evaluated the clinical utility of L-type Wako H. pylori antibody J test (Wako Ltx method) and SphereLight H. pylori antibody J test (Wako CLEIA method) for assessing the risk of gastric cancer. A total of 833 healthy adults without a history of Helicobacter pylori (Hp) eradication and gastrectomy were enrolled in this study. These subjects underwent upper gastrointestinal barium X-ray radiography (MDL) in January 2010 and upper gastrointestinal endoscopy (EGD) within 1 year thereafter. Anti-Hp antibody levels were measured using E-plate Eiken H. pylori antibody II kit (E-plate method) in 2010 and remeasured in 2015 by the Wako Ltx method and the Wako CLEIA method using preserved serum samples of the same specimens. Both Hp-positive agreement rate and Hp-negative agreement rate between the methods exceeded 90% (κ > 0.85). In the group of subjects with atrophic gastritis confirmed by MDL and EGD, the sensitivity and the specificity were 96.4% and 97.0% as measured by the Wako Ltx method and 95.5% and 97.2% as measured by the Wako CLEIA method, respectively. The false-negative rate of detecting anti-Hp antibody was 10.9% with the E-plate method, whereas the Wako Ltx method and the Wako CLEIA method produced false-negative rates of 3.6% and 4.5%, respectively (p < 0.001). Moreover, in the group of subjects with atrophic gastritis, the rates of group A according to the ABC classification (group pseudo-A) were 3.2% and 2.7% as measured by the Wako Ltx method and the Wako CLEIA method, respectively, which were significantly lower than 7.2% obtained with the E-plate method (p < 0.01). Both Wako Ltx and Wako CLEIA methods showed high positive and negative agreement rates with the conventional E-plate method, whereas in comparison with the E-plate method, both methods showed significantly lower false-negative rates of detecting anti-Hp antibody and significantly lower rates of group pseudo-A in the group of subjects with atrophic gastritis. Therefore, both Wako Ltx and Wako CLEIA methods are useful in daily practice, particularly in the case of ABC screening.
