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.