Circulating tumor cells as diagnostic markers of early gastric cancer and gastric precancerous lesions

Introduction: Circulating tumor cells (CTCs) may be potential diagnostic biomarkers of various malignancies including gastric cancer. This study aimed to evaluate whether CTCs could be used to facilitate the diagnosis of early gastric cancer (EGC) or precancerous gastric lesions. Methods: The diagnostic study included consecutive patients with EGC, gastric precancerous lesions or fundic gland polyps admitted to the Gastroenterology Department, Beijing Friendship Hospital Affiliated to Capital Medical University (National Center for Digestive Diseases) between October 2016 and January 2018. Results: A total of 92 patients were enrolled, including 57 patients with EGC, 14 patients with gastric precancerous lesions and 21 patients with fundic gland polyps (control group). CTCs were detected in 47.89% (34/71) of patients with EGC/gastric precancerous lesions and 4.76% (1/21) of patients with fundic gland polyps (P<0.001). CTC detection distinguished EGC/precancerous lesions from fundic gland polyps with an area under the ROC curve of 0.740 (95% confidence interval, 0.640-0.840; P=0.001), a sensitivity of 49.10%, a specificity of 95.00%, a positive predictive value of 97.00% and a negative predictive value of 64.90%. Conclusions: Peripheral blood CTCs are more common in patients with EGC or gastric precancerous lesions than in patients with fundic gland polyps. Measurement of CTCs may be a useful tool to aid the diagnosis of EGC and precancerous lesions.