Diagnostic accuracy of DNA methylation in detection of gastric cancer: a meta-analysis

Emerging studies demonstrate the diagnostic utility of DNA methylation-based blood test for gastric cancer. The aim of the meta-analysis is to evaluate the accuracy of blood DNA methylation markers for detecting patients with gastric cancer. A systematic literature search to November 2016 that evaluated DNA methylation markers utilizing blood specimen to detect gastric cancer were selected to derive pooled sensitivities and specificities. 32 studies including 4,172 patients (gastric cancer (N = 2,098), control (N = 2,074)) met the study criteria. Overall sensitivity of DNA methylation-based blood test for detecting gastric cancer was 57% (95% CI 50-63%); specificity was 97% (95% CI 95-98%). Among patients who received plasma-based testing, sensitivity was 71% (95% CI 59-81%); specificity was 89% (95% CI 78-94%). Among patients who received serum-based testing, sensitivity was 50% (95% CI 43-58%); specificity was 98% (95% CI 96-99%). Using multiple methylated genes had sensitivity of 76% (95% CI 64-84%); specificity of 85% (95% CI 65-95%). DNA methylation test had sensitivity of 55% (95% CI 47-64%) and specificity of 96% (95% CI 92-98%) for detecting TNM stage I+II gastric cancer. In conclusion, blood-based DNA methylation test had high specificity but modest sensitivity for detecting gastric cancer. Evaluating multiple methylated genes or using plasma sample may improve the diagnostic sensitivity.