Value of quantitative analysis of plasma epstein-barr virus DNA in monitoring recurrence and metastasis of nasopharyngeal carcinoma patients after radiotherapy

Objective To study the clinical value of quantitative analysis of plasma Epstein-Barr virus DNA(EBV DNA) in monitoring recurrence and metastasis of nasopharyngeal carcinoma patients after radiotherapy.Methods The plasma EBV DNA of eighty-one patients was analyzed by using fluorescent quantitative PCR technique and it was compared between clinical remission and recurrent or/and metastasis groups.Results 15.7%(8/51) of the clinical remission patients were positive for EBV DNA with median concentration of 0 copy/ml,whereas 93.3%(28/30) of the recurrent or/andmetastasis patients were detectable for plasma EBV DNA,with median concentration of 6 432 copies/ml.The detectable proportion and concentration in recurrent or/and metastasis patients were significantly higher than those in clinical remission patients(P0.001).Conclusions Detection of plasma EBV DNA may be a sensitive tumor marker for monitoring recurrence and metastasis of nasopharyngeal carcinoma patients after radiotherapy.