The Clinical significance of plasma Epstein-Barr virus DNA in nasopharyngeal carcinoma / 中华放射肿瘤学杂志

ABSTRACT

Objective It has been confirmed that Epstein-Barr virus ( EBV) is associated with the occurrence and development of the nasopharyngeal carcinoma ( NPC ) . We investigated the clinical significance of plasma concentrations of EBV-DNA in patients with NPC. Methods Since October,2013 to December,2016,471 patients were analyzed. The significantly associated between EBV-DNA before treatment and staging, tumor burden was analyzed. The survival rate of EBV-DNA before and after treatment was calculated. Results The median copies of pretreatment plasma EBV-DNA in patients is 137 copies,( range 0-494000) ,which is correlated with T stage,N stage,M stage,clinical stage and tumor burden load and that is statistically significant. Overall survival ( OS,P=0. 007) ,progression-free survival ( PFS,P=0. 011) and distant metastasis-free survival ( DMFS,P=0. 003) were significantly lower among patients with pretreatment plasma EBV-DNA more than 1300 copies/ml. Patients with detectable plasma EBV-DNA had significantly worse OS (P=0. 016),PFS (P=0. 000) and DMFS (P=0. 000) than patients with undetectable EBV-DNA after treatment. Cox multivariate analyze suggests that T stage and EBV-DNA after treatment were independent prognostic factors for OS,however the plasma EBV-DNA after treatment ( P=0. 006,0. 001) and N stage ( P=0. 037,0. 017) were independent prognostic factors for PFS and DMFS. Conclusions The plasma EBV-DNA level was significantly correlated with staging and tumor load before treatment in patients with NPC,and the prognosis of patients with higher copies before treatment could be worse. The plasma EBV-DNA after treatment is predictive for OS,PFS and DMFS.