A comparison study of different PCR assays in measuring circulating plasma Epstein-Barr virus DNA levels in patients with nasopharyngeal carcinoma CLINICAL CANCER RESEARCH Le, Q. T., Jones, C. D., Yau, T. K., Shirazi, H. A., Wong, P. H., Thomas, E. N., Patterson, B. K., Lee, A. W., Zehnder, J. L. 2005; 11 (16): 5700-5707


To compare the performance of three PCR assays in measuring circulating Epstein-Barr virus (EBV). DNA levels in nasopharyngeal carcinoma patients and to confirm its prognostic significance.Plasma from 58 newly diagnosed nasopharyngeal carcinoma patients were collected before, during, and every 3 to 6 months after radiotherapy. EBV DNA levels were determined by real-time quantitative PCR using primer/probe sets for polymerase-1 (Pol-1), latent membrane protein 2 (Lmp2), and BamHI-W. Pretreatment levels from the three assays were correlated with each other and serial measurements from the Pol-1 assay were correlated with clinical variables.Pol-1 was more accurate than BamHI-W in predicting EBV DNA concentrations in cell lines. Of the three assays, BamHI-W yielded the highest concentrations followed by Pol-1 in plasmas (n = 23). The correlation coefficient was 0.99 (P < 0.0001) for Pol-1 and Lmp2, 0.66 (P < 0.0001) for Pol-1 and BamHI-W, and 0.55 (P < 0.0001) for BamHI-W and Lmp2. Elevated pretreatment DNA levels as detected by Pol-1 were correlated with advanced nodal stage (P = 0.04) and overall stage (P = 0.028). There was no correlation between pretreatment EBV DNA levels and freedom-from-relapse or overall survival; however, there was a significant correlation between posttreatment levels and these variables. The 2-year freedom-from-relapse and overall survival rates were 92% and 94% for patients with undetectable, and 37% and 55% for those with detectable, posttreatment levels (P < 0.0001 and P < 0.002).The three PCR assays yielded similar results in detecting EBV DNA in plasmas. The Pol-1-detected posttreatment EBV DNA level was the strongest predictor for treatment outcomes.

View details for DOI 10.1158/1078-0432.CCR-05-0648

View details for PubMedID 16115906