Serum Helicobacter pylori CagA antibody may not be used as a tumor marker for diagnosing gastric cancer in east Asian countries.

Gastric cancer (GC) is a highly malignant cancer with increasing incidence and mortality worldwide. Serum Helicobacter pylori CagA antibody has been widely reported to play an important role in diagnosing GC. However, published data on this subject are inconclusive. Therefore, we performed a meta-analysis to evaluate the sensitivity and specificity of serum H. pylori CagA antibody in the diagnosis of GC. We conducted a comprehensive search to identify eligible related studies, in which the pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curves could be determined. A total of 12 studies including 1,524 cases and 3,324 controls who fulfilled all of the inclusion criteria were included for analysis. The summary estimates for serum H. pylori CagA antibody in the diagnosis of GC in these studies were pooled sensitivity 0.71 (95 % CI 0.69-0.73), specificity 0.40 (95 % CI 0.39-0.42), DOR 2.11 (95 % CI 1.55-2.8), and the area under the curve was 0.636. Our meta-analysis showed that serum H. pylori CagA antibody should not be used for detecting GC.