AIM:To explore the relationship of clinicopathological features and the distribution of neutrophils in the t umor mic roenvironment wi t h t he prognosis of cholangiocarcinoma.METHODS:Two hundred and fifty-four formalin-fixed and paraffin embedded tissue blocks were analyzed, including tissues from cholangiocarcinoma(n = 254), and tumor adjacent tissues(n = 238).Tissue sections were stained for CD15 using immunohistochemical staining.CD15 expression was detected to identify the distribution of neutrophils in the local tumor microenvironment.The neutrophil density of the tumor tissues and the adjacent tumor tissues was detected to reflect their inflammatory status.Clinical data and follow-up information of cholangiocarcinoma patients who underwent surgery from January 2004 to December 2010 were analyzed retrospectively.The relationship between clinicopathological features and the distribution of neutrophils with prognosis of the patients were analyzed.RESULTS:The positive expression level of CD15 was only significantly related to the TNM stage.CD15 expression was higher in tumor tissues than in adjacent tissues(73.6% vs 54.6%), with significant differences.Patients with high expression of CD15 had significantly shorter overall survival(OS) than those with low expression of CD15(median overall survival time 39.77 mo vs 16.87 mo, P = 0.008).Patients with high CD15 expression had significantly shorter disease free survival time(DFS) than those with low expression of CD15(median DFS 38.27 mo vs 16.83 mo, P = 0.029).COX multivariate analysis indicated that high CD15 expression in tumor tissues was an independent risk factor for predicting OS for patients with cholangiocarcinoma [P = 0.012, relative risk(RR) = 1.601], but it was not an independent risk factor for predicting DFS(P = 0.073, RR = 1.462).CONCLUSION:Patients with high CD15 expression in cancer tissues had shorter DFS and OS.High expression of CD15 is an independent risk factor for OS. AIM: To explore the relationship of clinicopathological features and the distribution of neutrophils in the umor mic roenvironment wi th he he prognosis of cholangiocarcinoma. METHODS: Two hundred and fifty-four formalin-fixed and paraffin embedded tissue blocks were analyzed, including tissues from cholangiocarcinoma (n = 254), and tumor adjacent tissues (n = 238). Tissue sections were stained for CD15 using immunohistochemical staining. CD15 expression was detected to identify the distribution of neutrophils in the local tumor microenvironment. The neutrophil density of the tumor tissues and the adjacent tumor tissues was detected to reflect their inflammatory status. Clinical data and follow-up information of cholangiocarcinoma patients who underwent surgery from January 2004 to December 2010 were analyzed retrospectively. The relationship between clinicopathological features and the distribution of neutrophils with prognosis of the patients were analyzed. RESULTS: The positive expression lev el of CD15 was only significantly related to the TNM stage. CD15 expression was higher in the tumor tissues than in adjacent tissues (73.6% vs 54.6%), with significant differences. Patients with high expression of CD15 had significantly shorter overall survival (OS) than those with low expression of CD15 (median overall survival time 39.77 mo vs 16.87 mo, P = 0.008) .Patients with high CD15 expression had significantly shorter disease free survival time (DFS) than those with low expression of CD15 (median DFS 38.27 mo vs 16.83 mo, P = 0.029). COX multivariate analysis indicated that high CD15 expression in tumor tissues was an independent risk factor for predicting OS for patients with cholangiocarcinoma [P = 0.012, relative risk (RR) = 1.601], but it was not an independent risk factor for predicting DFS (P = 0.073, RR = 1.462) .CONCLUSION: Patients with high CD15 expression in cancer tissues had shorter DFS and OS. High expression of CD15 is an independent risk factor for OS.