Objective To investigate the clinical significance of changes of serum EB virus capsid antigen IgA（EBV VCA-IgA）antibodies in the detection before and after the treatment of locally advanced nasopharyngeal carcinoma and its relation with the clinical features of patients.Methods Medical records of 51 cases of patients with locally advanced nasopharyngeal carcinoma pathologically confirmed from March to October 2014 in the first Affiliated Hospital of Fujian Medical University were retrospectively analyzed to explore the relation between levels of pre-treatment serum EBV VCA-IgA and patients′clinical features and compare the EBV VCA-IgA levels before and after radiotherapy.Results Before treatment

the value of S/CO of EBV VCAIgA was 3.88（2.14

6.05）

the positive rate of EBV VCA-IgA antibodies was 94.1%

and there were no significant differences of positive rates in groups of different gender

age

T stage

N stage

overall stage and smoking history.20 cases of patients were reexamined EBV VCA-IgA after two courses of induction chemotherapy before radiotherapy;the value of S/CO of EBV VCA-IgA after chemotherapy was 3.99（2.09

5.22）

lower than 4.09（2.16

6.20）of before chemotherapy

but the difference was not statistically significant（Z=-0.845

P=0.398）;the positive rate of EBV VCA-IgA antibodies was 85.0%

less than 95.0% of before chemotherapy and the difference was not statistically significant（χ

2

=-0.278

P=0.598）.31 cases of patients were reexamined EBV VCA-IgA after two courses of induction chemotherapy and radical radiotherapy;the value of S/CO of EBV VCA-IgA after radiotherapy was 2.30（1.35

5.20）

lower than 3.91（2.20

6.43）of before treatment

but the difference was not statistically significant（Z=-1.744

P=0.081）;the positive rate of EBV VCA-IgA antibodies after chemotherapy and radiotherapy was 87.1%

less than 93.5% of before chemotherapy and the difference was not statistically significant（χ

2

=-0.185

P=0.668）.Conclusions The reference value of EBV VCA-IgA in evaluating the treatment efficacy of locally advanced nasopharyngeal carcinoma is limited and its clinical factors of pre-treatment EBV VCA-IgA levels remain to be further studied.