Assessment of EBV antibodies and EBV-DNA in the diagnosis and stages of nasopha-ryngeal carcinoma / 中国肿瘤临床

ABSTRACT

Objective:To evaluate the efficacy of Epstein-Barr nuclear antigen 1/immunoglobulin A (EBNA1/IgA), BamH1 Z transactivator/IgA (Zta/IgA), capsid antigen/IgA (VCA/IgA), and Epstein-Barr virus deoxyribonucleic acid (EBV-DNA) in detecting different stages of na-sopharyngeal carcinoma (NPC). The relationship between the EBV markers and stages of NPC was also analyzed. Methods:Blood sam-ples of 152 untreated patients with NPC and 675 healthy subjects were collected.ELISA was used to detect the serum levels of EBNA1/IgA, Zta/IgA, and VCA/IgA. Fluorescence quantitative PCR (FQ-PCR) was used to detect the plasma levels of EBV-DNA. ROC and correla-tion analyses were employed to assess the detection assays for NPC diagnosis. The positive rates of EBV markers in NPC patients in dif-ferent stages were analyzed statistically. Results: The positive rates of EBNA1/IgA, Zta/IgA, VCA/IgA, and EBV-DNA in NPC patients were higher than those in the healthy individuals. The expression of EBNA1/IgA was relatively high in early NPC. The sensitivity of EB-NA1/IgA was 77.8%. In advanced NPC, the level of EBV-DNA was high, and the sensitivity of EBV-DNA was 88.8%. The specificity of EBV-DNA and EBNA1/IgA could reach more than 96%. The combination of EBV-DNA and EBNA1/IgA showed the best diagnostic value, with a sensitivity of 92.1%(early stage 82.5%, advanced stage 98.9%) and a specificity of 96.9%. The positive rates of EBV-DNA were positively associated with the NPC clinic stage and N stage. The positives rates of Zta/IgA were positively associated with the NPC N stage. Conclusion:The best single index for NPC screening in an asymptomatic population is EBNA1/IgA. EBV–DNA is an ideal index for auxiliary diagnostics of advanced NPC. The combination of EBV-DNA and EBNA1/IgA shows the best diagnostic value. EBV-DNA is an important index in the stage and illness monitoring of NPC. Zta/IgA can indirectly reflect the character of lymph node metastasis, and it may be useful in assessment of NPC surveillance.