Specific detection of Epstein-Barr virus microRNAs in plasma samples from nasopharyngeal carcinoma patients: Correlation with tumor mass assessed by MRI.

6079 Background: Epstein-Barr virus (EBV) microRNAs of the BART family can be detected in the plasma of at least a fraction of nasopharyngeal carcinoma (NPC) patients. Our aim was to investigate the specificity of plasma BART detection in NPC patients and the correlation with viral DNA load and/or clinical characteristics. Methods: Hsa miR484 and 4 miR-BARTs (ebv-miR BART 2-5p, 5, 9 and 18) were assessed by RT-PCR following RNA extraction in 37 plasma samples including 20 NPC, 8 non-NPC head and neck squamous cell carcinoma (SCC) patients and 9 healthy EBV carriers. EBV DNA copy numbers (viral load) were measured in the same samples. To explore correlations of BART concentrations with tumor mass, MRI-based volume analysis was designed and performed on a subset of 13 patients with non metastatic NPC. In addition, longitudinal variations of BART concentrations were studied in 9 NPC patients for whom we had sequential plasma samples. Results: The cellular hsa miR-484 was detected in all plasma samples with a...