The evolution of EBV DNA as a biomarker in nasopharyngeal carcinoma immunotherapy: a bibliometric and knowledge mapping analysis

BACKGROUND: The treatment response to immunotherapy for nasopharyngeal carcinoma (NPC) exhibits significant interindividual variability. As a biomarker closely associated with NPC, Epstein-Barr virus (EBV) DNA holds substantial importance in this research context. However, there is still an insufficient comprehensive assessment of the current research status and development trends of EBV DNA as a biomarker for NPC immunotherapy in the existing literature. METHODS: In this study, we conducted a bibliometric analysis of 164 original English articles and reviews on EBV DNA as a biomarker in NPC immunotherapy, utilizing the WoSCC database along with CiteSpace and Bibliometrix software tools. The analysis and visualization were performed from the following aspects: publication trends, country/region distribution, keyword co-occurrence networks, patterns of co-authorship and co-citation, and the evolution of cited journals and themes. RESULTS: Since 2017, research in this area has developed rapidly, with China and the United States being the two main contributors. The primary research hotspots include PD-1 inhibitors, antitumor activity, and exploration of molecular mechanisms. The field showed a clear shift from traditional themes centered on tumor burden, recurrence, radiotherapy, and prognosis toward immunotherapy-related themes, including PD-1, clinical trials, and dynamic monitoring. CONCLUSIONS: EBV DNA is increasingly viewed as a dynamic biomarker that integrates viral biology, tumor burden, and treatment response in NPC. Plasma EBV DNA is mainly derived from apoptotic or necrotic EBV-positive tumor cells, making its baseline level a surrogate of systemic tumor burden. Its kinetic changes during immunotherapy indicate tumor control, while fluctuations or elevations reflect combined effects of tumor destruction, viral reactivation and host immunity. Its value in prognostic stratification and dynamic monitoring has been relatively well established. Broader clinical use will require assay standardization and prospective validation.