Diagnostic value of lymph node EBV-DNA detection in cervical lymph node metastasis of nasopharyn-geal carcinoma

Abstract

Objective To evaluate the diagnostic value of lymph node fine-needle aspiration (FNA) Epstein-Barr virus (EBV)-DNA concentration detection in nasopharyngeal carcinoma (NPC) cervical lymph node metastasis. Methods From August to December 2016, 36 cases of NPC and 9 cases of other tumors (not correlated with EBV infection) were enrolled in this study at the Sun Yat-sen University Cancer Center. All patients received magnetic resonance images (MRI), plasma and cervical lymph node FNA EBV-DNA detection. Results The median concentration of EBV-DNA in FNA fluid (1.39×105 copies/ml) in cervical lymph node metastasis was significantly higher than that in plasma (2.00×103 copies/ml), with a significant diffe-rence (χ2=16.723, P=0.004). The diagnosis sensitivity, specificity, accuracy of the lymph node FNA fluid of EBV-DNA were 86.2% (25/29), 71.4% (10/14) and 81.4% (35/43) respectively, which were better than those of MRI [72.4% (21/29), 50.0% (7/14) and 65.1% (28/43) respectively] and plasma EBV-DNA [55.2% (16/29), 71.4% (10/14) and 60.5% (26/43) respectively]. The area under the curve (AUC) of level Ⅰb cervical lymph node metastasis was calculated, and FNA fluid EBV-DNA (AUC=0.688) was better than MRI (AUC=0.583), with a significant difference (Z=2.476, P=0.008). The EBV-DNA concentration in FNA fluid in cervical lymph node metastasis of patients with other tumors (no correlated with EBV infection) was 0 copy/ml. Conclusion FNA fluid EBV-DNA may improve the diagnostic sensitivity of cervical lymph node metastasis in nasopharyngeal carcinoma, and help to explore the clinical target volume neck nodes at level Ⅰb cervical lymph node in radiotherapy. Key words: Nasopharyngeal neoplasms; Lymphatic metastasis; Biopsy, fine-needle; Epstein-Barr virus DNA