Distribution Analysis for Antibody Levels of Epstein-Barr Virus VCA/IgA,Rta/IgG and EBNA1/IgA in Different Classified Populations from High Risk Area of Nasopharyngeal Carcinoma

Objective To investigate the distribution of Epstein-Barr virus(EBV)antibody levels of immunoglobulin A(Ig A)against EBV capsid antigens(VCA),IgG against BRLF1 transcription activator(Rta)and IgA against EBV nuclear antigen-1(EBNA1)in nasopharyngeal carcinoma(NPC),non-NPC ENT patients and healthy population from high risk area of NPC.Methods Serum samples derived from211 untreated patients with NPC,203 non-NPC ENT patients and 210 healthy volunteers were examined for the presence of VCA/IgA by immunoenzymatic assay,Rta/IgG and EBNA1/IgA by enzyme-linked immnunosorbent assay(ELISA).Rank-sum test,receiver operating characteristics(ROC)curve and multinomial logistic regression were applied to analyze the research data.Results The antibody levels of VCA/IgA,Rta/IgG and EBNA1/IgA in NPC were significantly higher than those in non-NPC ENT patients and healthy population,respectively(P0.001).The antibody levels of Rta/IgG and VCA/IgA in non-NPC ENT patients were also significantly higher than those in healthy population(P0.001).The results from ROC curve analysis in non-NPC ENT patients and healthy population showed that the areas under ROC curve of VCA/IgA and Rta/IgG had statistical significance(P0.05),which were 0.565 and 0.604,respectively.According to the multinomial logistic regression model analyzed with age,gender and three EBV antibodies,the correct percentages predicted for NPC,non-NPC ENT patients and healthy population were 95.3%,70.9%and 55.2%,respectively.Conclusions There are a certain difference of antibody levels of EBV Rta/IgG and VCA/IgA of non-NPC ENT patients and healthy population from high risk area of NPC.It is feasible to set different critical values of EBV antibodies for facilitating population screening and clinical diagnosis of NPC.