Clinicopathological and prognostic value of chemokine receptor CCR7 expression in esophageal squamous cell carcinoma: a meta-analysis

Background: The prognostic significance of CC chemokine receptor type 7 (CCR7) for the survival of patients with esophageal squamous cell carcinoma (ESCC) remains controversial. Objective: Our aim was to investigate the influence of CCR7 on clinicopathological features and survival outcome in ESCC by performing a meta-analysis. Methods: A comprehensive search in the Embase, Web of Science, PubMed, CNKI, and WanFang databases (up to October 2017) was performed for relevant studies using various search strategies. The odds ratio (OR) and 95% confidence intervals (95% CIs) were used to evaluate the association between CCR7 expression and the clinicopathological features and overall survival rate of ESCC. A sensitivity analysis was carried out to estimate the stability of our results. Results: Eight eligible studies consisting of data for 722 ESCC patients were collected for our meta-analysis. The results reveal that CCR7 expression is associated with depth of invasion (OR: 0.37, 95% CI: 0.19-0.74, P=0.005), TNM stage (OR: 0.25, 95% CI: 0.16-0.39, P<0.001), and lymph node metastasis (OR: 5.01, 95% CI: 3.47-7.22, P<0.001). Four studies (consisting of data for 528 patients) were evaluated for association between CCR7 expression and overall survival (OS), revealing that high CCR7 expression is correlated with poor prognosis in esophageal squamous cell carcinoma patients (HR: 2.06, 95% CI: 1.56-2.71, P<0.001). Funnel plots and Begg's test indicated that the publication bias of these eligible studies was insignificant. The sensitivity analysis revealed that no study substantially affected pooled OR/HR. Conclusions: Meta-analysis shows that high CCR7 expression is significantly associated with negative prognosis of ESCC patients in the Asian population.