Increased expression of CD55 correlates with tumor progression and poor prognosis in nasopharyngeal carcinoma.

PURPOSE To analyze the expression of complement delay-accelerating factor (CD55) in nasopharyngeal carcinoma and its correlation with clinicopathologic features, including survival rate. METHODS Eighty-two nasopharyngeal carcinoma tissues were evaluated for CD55 expression using immunohistochemistry. The association between CD55 expression and various clinicopathological characteristics including overall survival was analyzed. RESULTS Immunohistochemical analysis revealed that the protein expression of CD55 detected in nasopharyngeal carcinoma tissues was higher than that in the normal nasopharyngeal tissue (P=0.003). In addition, high levels of CD55 protein were positively correlated with the status of lymph node metastasis (P=0.02) and distant metastasis (P=0.01), and clinical stage (P=0.002) of nasopharyngeal carcinoma patients. Patients with positive CD55 expression had a significantly shorter overall survival time than did patients with negative CD55 expression (P=0.001). Multivariate analysis suggested that the expression pattern of CD55 protein was an independent prognostic indicator (P=0.009) for the survival of patients with nasopharyngeal carcinoma. CONCLUSION The data from this study suggest, for the first time, that CD55 is frequently expressed in nasopharyngeal carcinoma and its expression is associated with decreased patient survival; therefore, CD55 expression may be a potential unfavorable prognostic factor for patients with nasopharyngeal carcinoma.