OBJECTIVETo explore the correlations of circulating tumor cells (CTCs) and disseminated tumor cells (DTCs) with the clinicopathological characteristics, prognostic events, and survival outcomes in esophageal cancer (EC) patients.

METHODSThe PubMed, Web of Science, Embase database and Cochrane database were searched for studies reporting the outcomes of interest. The studies were selected according to established inclusion/exclusion criteria. Meta-analysis of the studies was performed using Review Manager 5.3 and Stata12.0 software with the odds ratio (OR), risk ratio (RR) , hazard ratio (HR) , and 95% confidence interval (95% CI) as the effect indexes.

RESULTSNineteen studies involving a total of 1766 patients were included in the analysis. Significant correlations of CTCs and DTCs were found with the clinicopathological parameters including the tumor stage (OR=1.95), depth of invasion (OR=1.99), lymph node metastasis (OR=2.44), distal metastasis (OR=5.98), histological differentiation (OR=1.67) and lymphovascular invasion (OR=4.48). CTCs and DTCs were also correlated with the prognostic events including relapse (RR=6.86) and metastasis (RR=3.22) and with the survival outcomes including the overall survival (OS) overall analysis (HR=3.46) and disease-free survival/progression-free survival (DFS/PFS) overall analysis (HR=3.00).

CONCLUSIONCTCs and DTCs are significantly associated with an advanced tumor stage, depth of tumor invasion, lymph node metastasis, distant metastasis before therapy, differentiation, lymphovascular invasion, relapse and metastasis in patients with EC. They are also significantly correlated with a poorer survival for OS and DFS/PFS to serve as clinical and prognostic predictors in patients with EC.