DISTRIBUTION OF EPSTEIN-BARR VIRAL LOAD IN SERUM OF INDIVIDUALS FROM NASOPHARYNGEAL CARCINOMA HIGH-RISK FAMILIES IN TAIWAN
Resource
INTERNATIONAL JOURNAL OF CANCER v.118 n.3 pp.780-784
Journal
INTERNATIONAL JOURNAL OF CANCER
Journal Volume
v.118
Journal Issue
n.3
Pages
780-784
Date Issued
2006
Date
2006
Author(s)
CHEN, CHIEN-JEN
CHEN, JEN-YANG
CHENG, YU-JUEN
HSU, WAN-LUN
LIU, MEI-YING
Abstract
The utility of EBV load as a tumor marker in nasopharyngeal carcinoma (NPC) patients suggests that it might also serve as a screening test for individuals who are at high risk for developing NPC. We previously demonstrated that unaffected individuals from high-risk families had elevated anti-EBV antibody levels compared to community controls. In this study, we measured EBV load using 2 different real-time PCR assays (targeting BamH1W and polymerase gene sequences, respectively) carried out in 2 independent research labs in serum samples from 19 untreated NPC cases, 11 healthy community controls and 100 unaffected individuals from families in which 2 or more individuals were affected with NPC. EBV genomes were detectable in 68% of NPC cases by the EBV BamH1W assay and in 74% by the EBV polymerase assay ( kappa = 0.64). Patients with stage III or IV disease had significantly higher EBV load compared to those with stage I or II disease (p = 0.008). EBV DNA was detected in a single community control sample by the EBV BamH1W assay and in none of the samples by the EBV polymerase assay. Only one of 100 unaffected family members tested positive by both assays. An additional 14 were positive by only one of the 2 EBV load assays used and usually in only one of the duplicate wells tested, all with very low viral loads (3-50 copies/ml). In addition, EBV load did not correlate with EBV serology results (anti-VCA, anti-DNase, anti-EBNA-1) among these unaffected family members. In conclusion, our study suggests limited clinical utility of the EBV load test, in its current configuration, to screen individuals from high- risk families. Should a more sensitive or specific molecular assay be developed that is capable of detecting and distinguishing tumor-derived EBV genomes or gene products from true negatives, it could be evaluated as a possible screening tool for asymptomatic and early-stage NPC. (c) 2005 Wiley-Liss, Inc.
Subjects
Epstein-Barr viral load
nasopharyngeal carcinoma
high-risk family
Epstein-Barr virus serology
Type
journal article