Expression of CCR7 in squamous cell carcinoma of the esophagus after esophagectomy:correlation with lymph node metastasis and prognosis

Abstract

Objective To investigate the expression of chemokine receptor CCR7 and its correlation with lymph node metastasis and prognosis in esophageal cancer after esophagectomy. Methods One hundred and eighty-four patients with middle third squamous cell carcinoma of the esophagus were enrolled in this study. All patients underwent operation in Provincial Hospital Affiliated to Shandong University between June, 2003 and June, 2005. The expression of CCR7 was detected by immunohistochemistry. All statistic analyses were performed with SPSS 13.0 statistical software. According to the clinico-patho-logic factors, the difference of CCR7 expression was compared by x2 test. Kaplan-meier method was performed to calculate the survival rate, Cox regression multivariate analysis was performed to determine independent prognostic factors. Results The expression rate of CCR7 in stage Ⅰ , stage Ⅱ and stage Ⅲ patients was 25.0 % , 70.3% and 85.5% , respectively. The difference of CCR7 expression between stage Ⅱ and stageⅢ was statistically significant (x2 =5.0, P =0.02). The CCR7 expression rate in T1, T2 and T3 patients was 33.3% , 64.9% and 80.9% , respectively. The difference of CCR7 expression between T2and T3 was statistically significant (x2 =5.4, P =0.01). The level of expression of CCR7 in patients with lymph node metastasis was significantly higher than those without metastasis (x2 =10.8, P = 0.00). The 5-year survival rate instage Ⅰ , stage Ⅱand stage Ⅲ patients was 100.0% , 38. 3% and 22.4% , respectively. The 5-year survival rate in patients with CCR7 overexpression was significantly lower than those without CCR7 overexpression (x2 = 23.7, P = 0.00). The 5-year survival rate in T2, T3, NO and N1 patients with CCR7 overexpression was significantly lower than those without CCR7 overexpression The result of Cox analysis demonstrated that T , N and CCR7 overexpression were independent prognostic factors. Conclusion CCR7 expression was detected in esophageal squamous cell carcinoma and was found to be significantly associated with T stage,N stage and lymph node metastasis. The patients with CCR7 expression was significantly lower the 5-year survival rate than without CCR7 expression. T stage, lymph node metastasis and CCR7 expression were independent prognostic factors. Key words: Esophageal neoplasms; Lymphatic metastasis; Surgical procedures; Chemokine; Receptor CCR7