Vasculogenic mimicry is associated with increased tumor-infiltrating neutrophil and poor outcome in esophageal squamous cell carcinoma

Purpose: Vasculogenic mimicry (VM) is known to be a mechanism to nourish the tumor, but little is known about its prognostic significance in esophageal squamous cell carcinoma (ESCC). We characterized the predictive relevance of VM expression and tumor-infiltrating neutrophil (TIN) density in patients with resectable ESCC. Methods: We retrospectively collected clinicopathologic characteristics of 117 esophageal cancer (EC) patients undergoing complete resection and without preoperative therapy. Immunohistochemistry was used to detect the expression of E-cadherin and CD66b. CD34/periodic acid-schiff (PAS) double staining was used to detect the expression of VM. Results: VM expression was observed in 56 (47.9%) patients. VM was negatively correlated with E-cadherin (correlation coefficient=-0.364, P<0.001) and was positively correlated with infiltration of CD66b neutrophil (correlation coefficient =0.421, P<0.001). VM and CD66b(+) neutrophil infiltration are important markers for poor overall survival and disease-free survival. Multivariate analysis showed that VM, CD66b(+) neutrophil infiltration, pathologic tumor node metastasis (TNM) (pTNM) stage, and tumor differentiation are significant independent prognostic predictors in ECs (P=0.001, 0.025, 0.001, 0.011, respectively). VM expression is identified in similar to 7.9% of ESCC, and it is associated with poor outcome and increased TIN. Conclusion: TIN is an important factor for VM formation. Therefore, studies of invasive ability of EC in patients with VM could supply significant information for therapeutic strategy.