| Objective:To explore the correlation of EB virus antibody and nucleic acid detection with nasopharyngeal carcinoma,and to study the applications of EB virus EA-IgA,Rta-IgG,VCA-IgA and EB virus DNA in the early diagnosis,treatment and the screening of nasopharyngeal carcinoma.Material and methods:A total of 100 patients who were firstly diagnosed with nasopharyngeal carcinoma in the First People's Hospital of Chenzhou were collected from January 2016 to December 2018,without distant metastasis,or treatment with concurrent chemotherapy and radiotherapy.Those patients were selected as the experimental group,100 outpatient patients with nasopharyngitis and 100 healthy persons were selected as Control group.The fasting venous blood of the experimental group was collected before treatment and after the treatment,respectively.The fasting venous blood of the control group was collected on the day of physical examination or outpatient.ELISA method was used to detect the antibodies of EB virus EA-IgA,Rta-IgG and VCA-IgA,and qRT-PCR(quantitative fluorescence real-time polymerase chain reaction)was used to detect EBV DNA in the plasma of patients with nasopharyngeal carcinoma.From December 2017 to December 2019,8243 volunteers were recruited to screen nasopharyngeal cancer in our hospital's health management center.Two tubes of 5ml fasting venous blood,each tube were collected from the subjects for detection of EB virus antibody and nucleic acid,respectively.The person with at least one positive result of the EB antibodies VCA-IgA,Rta-IgG,EA-IgA and positive EBV DNA at the same time,were subjected two consecutive tests for detecting plasma EBV DNA(60 days each interval).The patients with positive EBV DNA at the three consecutive times were defined as high-risk subjects,and were followed up visit for 2 years.Those patients were performed for regular detection of EB virus antibodies and EB virus DNA,and nasopharyngeal MRI or nasopharyngoscopy(pathological biopsy for abnormal patients).The data were analyzed using SPSS 20.0 statistical software.The qualitative data analysis adopted the chi-square test,which was shown by the rate(%).The results of quantitative data results were accordance with normal distribution.Therefore,the quantitative data was analyzed by t test,expressed as mean ± standard deviation.Non-normal distribution was analyzed by non-parametric test,described by median and quartile spacing [M(25%,75%)].Before and after treatment,quantitative analysis was performed by using paired t test.P <0.05 indicated that the difference was statistically significant.Results:1.The AUC,sensitivity,specificity and Youden index of EBV VCAIgA respectively were 0.773,74%,80.5% and 0.545;the AUC,Sensitivity,specificity,Youden index of EBV EA-IgA respectively were 0.768,79%,74.5% and 0.535;the AUC,sensitivity,specificity,Youden index of EBV Rta-IgG respectively were 0.742,63%,85.5%,and 0.485;the AUC,sensitivity,specificity,and Youden index of EBV DNA were 0.875,80%,95%,and 0.750,respectively.Among them,the diagnostic efficacy of EBV DNA was the best.2.When the cut-off value of EB virus DNA was 100 copies / ml,it was the better in the linear range of reagent detection in this study,and its sensitivity,specificity,Youden index,and AUC were 80%,95%,0.750,and 0.875,respectively.3.In the combined diagnosis,EA-IgA / Rta-IgG / VCA-IgA + EBV DNA has the best diagnostic efficacy.When the cut-off value of EB virus DNA was 100 copies / ml,the sensitivity,specificity,and AUC of the combined diagnosis were 77%,97.5%,and 0.873,respectively.4.According to the RECIST efficacy evaluation criteria,the patients with nasopharyngeal carcinoma were divided into remission group(CR + PR)and non-remission group(SD + PD).Through the comparative analysis of changes of the four indexes of patients with nasopharyngeal carcinoma in two groups before and after treatment,the average level of log(EBV DNA)in the non-remission group were all higher than that in the remission group(P <0.05);In both groups,the level of log(EBV DNA)before treatment was higher than that after treatment(P <0.05).The mean level of EA-IgA before treatment or after treatment was not statistically different between the remission group and the non-remission group(P> 0.05),but the level of EA-IgA in pre-treatment remission group was higher than that in post-treatment remission group(P <0.05);however there was no statistical difference between pre-treatment and post-treatment in the non-remission group(P> 0.05).The mean levels of VCA-IgA and RtaIgG were not significantly different between the remission group and the non-remission group(P> 0.05),and there was no statistical difference between the two groups before and after treatment(P> 0.05).5.The level of log(EBV DNA)before or after treatment of the patients with nasopharyngeal carcinoma recurrence and metastasis group was higher than that in the non-recurrence or metastasis group(P <0.05);In both groups,the level of log(EBV DNA)before treatment was higher than that after treatment(P <0.05).The mean level of EA-IgA was not statistically different between the recurrence and metastasis group and the non-recurrence or metastasis group before treatment and after treatment(P> 0.05);the level of EA-IgA before treatment was higher than that after treatment in the non-recurrence or metastasis group(P <0.05).There was no statistical difference between pre-treatment and post-treatment in the recurrence and metastasis group(P> 0.05).6.Among the 8243 enrolled subjects,10 of them met the condition that at least one of the three antibodies of EBV VCA-IgA,Rta-IgG,and EA-IgA was positive,and 3 consecutive tests of EBV DNA(each interval of 60 days)were positive.Among the 10 cases,5 persons has been diagnosed as NPC,and the other 5 persons were being followed up.The remaining subjects were negative in screening,14 of which were lost to follow-up,and the 8219 subjects were still being followed up.No nasopharyngeal cancer patients were found in these subjects.At present,the sensitivity of this early screening program is 100% and the specificity is 99.94%.Conclusion1.In this study,the EBV DNA cut off value of 100 copies / ml has a better diagnostic efficacy for NPC.2.This study shows that EBV EA-IgA may be one of the sensitive indicators for monitoring the efficacy and prognosis of nasopharyngeal carcinoma.3.The detection of EB virus antibody and EBV DNA for three consecutive times(60 days each interval)can be used for early screening of nasopharyngeal cancer in healthy people,which can helps to increase the sensitivity and specificity for the early screening. |
PDF Full Text Request