Quantification of Epstein-Barr virus (EBV) cell-free DNA (cfDNA) is commonly used in clinical settings as a circulating biomarker in nasopharyngeal carcinoma (NPC), but there has been no comparison with circulating tumour cells (CTCs).Our study aims to compare the performance of CTC enumeration against EBV cfDNA quantitation through digital PCR (dPCR) and quantitative PCR. 74 plasma samples from 46 NPC patients at baseline and one month after radiotherapy with or without concurrent chemotherapy were analysed. CTCs were captured by microsieve technology and enumerated, while three different methods of EBV cfDNA quantification were applied, including an in-house qPCR assay for BamHI-W fragment, a CE-IVD qPCR assay (Sentosa ® ) and a dPCR (Clarity ™ ) assay for Epstein-Barr nuclear antigen 1 (EBNA1). EBV cfDNA quantitation by all workflows showed stronger correlation with clinical stage, radiological response and overall survival in comparison with CTC enumeration. The highest detection rate of EBV cfDNA in pre-treatment samples was seen with the BamHI-W qPCR assay (89%), followed by EBNA1-dPCR (85%) and EBNA1-qPCR (67%) assays. Overall, we show that EBV cfDNA outperforms CTC enumeration in correlation with clinical outcomes of NPC patients undergoing treatment. Techniques such as dPCR and target selection of BamHI-W may improve sensitivity for EBV cfDNA detection.Nasopharyngeal carcinoma (NPC) is a malignant cancer of the nasopharynx, which is particularly common in parts of Southern China, South East Asia and North Africa 1 . Due to high rates of Epstein-Barr virus (EBV) nucleic acid detection in NPC, non-invasive approaches to diagnosis have focused on EBV as a target [2][3][4] . Post-treatment Epstein-Barr virus (EBV) cell-free DNA (cfDNA) levels have been demonstrated to correlate with NPC prognosis and recurrence 5,6 . EBV cfDNA can be quantified in the form of EBV single-copy genes; EBNA1, LMP2 and Pol-1, or multiple-repeat fragments; BamHI-W 7 . As there are six to twenty copies of BamHI-W per EBV genome 8 , higher sensitivity is expected in BamHI-W quantification assays. However, the variability of BamHI-W copy numbers in different EBV isolates has been considered a challenges in assay comparison and standardization between laboratories 7, 8 . CTCs represent a circulating biomarker which has been extensively studied in many cancer types including breast, lung and colorectal cancer [9][10][11][12] . Due to challenges including platform costs and standardization, much

No abstract

diagnosed with metastatic disease and 13.3% died from the disease during the study period, accounting for 2.4% of all cancer deaths. Conclusion: Pancreatic cancer remains a significant public health issue. Early diagnosis is difficult because the disease is asymptomatic in its early stages "silent disease". ctic body radiation therapy (SBRT) for locally advanced cancer (LAPC)

No abstract

No abstract