Circulating Plasma Epstein–Barr virus DNA Load During the Follow-up Periods Predicts Recurrence and Metastasis in Nasopharyngeal Carcinoma

Abstract

<jats:title>Abstract</jats:title> <jats:p>PURPOSE Epstein Barr virus DNA (EBV DNA) load has been identified as a prognostic factor in nasopharyngeal carcinoma, while the dynamic changes in the long period have not been explored. In this study, we evaluated EBV DNA kinetics and its role in the survival. METHODS We conducted a retrospective review of 900 NPC patients. Plasma EBV DNA levels were measured at various time points after treatment. The correlations of EBV kinetics with recurrence and metastasis were analyzed. After stratifying patients according to the EBV results, survival was compared using Kaplan–Meier estimates. 12 and 24-month landmark analyses for OS data were performed according to the EBV groups. RESULTS Patients with post-EBV &lt; 2,500 copies/mL achieved better survival than the higher ones. Furthermore, patients with continuously elevated EBV DNA had significantly poorer OS (HR: 2.542, 95%CI: 2.077–3.111, P &lt; 0.001), DMFS (HR: 2.970, 95%CI: 2.392–3.687, P &lt; 0.001), LRFS (HR: 1.699, 95%CI: 1.072–2.692, P = 0.013), and PFS (HR:2.535, 95%CI: 1.987–3.233, P &lt; 0.001) than patients with continuously normal EBV or those with elevated levels at any time-point. The 5-year OS with elevated EBV was lower than the remission group by the 12 and 24-month landmark analysis. CONCLUSIONS Elevated EBV DNA after treatment was a better predictive indicator of survival than the baseline concentrations. Furthermore, continuously elevated EBV DNA after treatment indicated recurrence, metastasis and unfavorable prognosis for NPC. In addition, EBV DNA was predictable no matter how long the follow-up time.</jats:p>