Prognostic implications of circulating Epstein–Barr virus DNA for extranodal natural killer/T-cell lymphoma, nasal type: a meta-analysis

INTRODUCTION: To evaluate the prognostic value of circulating Epstein-Barr virus DNA for extra-nodal natural killer/T-Cell lymphoma, nasal type (ENKTL), we performed a meta-analysis of published studies that provided survival information with pre-/post-treatment circulating EBV DNA. METHODS: Eligible studies that discussed prognostic significance of circulating EBV DNA in ENKTL were included. Random effects models were applied to obtain the estimated hazard ratios and 95% confidence intervals to evaluate prognostic significance (OS and DFS/PFS). Eleven studies covering a total of 562 subjects were included in this analysis. RESULTS: The summary HRs and 95% CIs of pre-treatment EBV DNA for OS and PFS/DFS were 4.43 (95% CI 2.66–7.39, P<0.00001) and 3.12 (95% CI 1.42–6.85, P=0.005), respectively. The corresponding HRs and 95% CIs of post-treatment EBV DNA for OS and PFS/DFS were 6.28 (95% CI 2.75–14.35, P<0.0001) and 6.57 (95% CI 2.14–20.16, P=0.001). Subgroup analyses indicated a strong trend of prognostic powers with pre-/post-treatment EBV DNA. CONCLUSION: With the present evidence, circulating EBV DNA consistently correlated with poorer prognosis in patients with ENKTL which need further investigation in large-scale clinical studies.