Comparison of the prognostic impact of serum anti-EBV antibody and plasma EBV DNA assays in nasopharyngeal carcinoma.
OBJECTIVE
Nasopharyngeal carcinoma (NPC) has been proven as an Epstein-Barr virus (EBV)-associated cancer. Serum anti-EBV antibodies and plasma EBV DNA have been investigated as surrogate markers for NPC. A comparison of the prognostic impacts of both assays has never been reported.


METHODS
Paired serum and plasma samples from 114 previously untreated NPC patients were collected and subjected to an immunofluorescence assay for immunoglobulin (Ig)A and IgG antibodies against the viral capsid antigen (VCA) and a real-time quantitative polymerase chain reaction assay for EBV DNA measurement. The effects of both assays on patient prognosis were thoroughly investigated.


RESULTS
Relapsed patients had significantly higher pretreatment EBV DNA concentration than patients without relapse (p = 0.0006). No associations of VCA-IgA (p = 0.9669) or VCA-IgG (p = 0.6125) were observed between patients with and without relapse. The 4-year overall survival (60.3% vs. 93.1%, p < 0.0001) and relapse-free survival rates (54.4% vs. 77.9%, p = 0.0009) were significantly lower in patients with higher pretreatment EBV DNA load than in those with lower EBV DNA load. Patients with persistently detectable EBV DNA after treatment had significantly worse 4-year overall (30.8% vs. 84.6%, p < 0.0001) and relapse-free survival rates (15.4% vs. 74.0%, p < 0.0001) than those with undetectable EBV DNA. The VCA-IgA and VCA-IgG titer could not predict survivals (all p > 0.1). Cox multivariate analyses also showed the same results.


CONCLUSIONS
Plasma EBV DNA is superior to serum EBV VCA antibodies in prognostic predictions for NPC.
Twu
Chih-Wen
CW
Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei.
Wang
Wen-Yi
WY
Liang
Wen-Miin
WM
Jan
Jian-Sheng
JS
Jiang
Rong-San
RS
Chao
Jeffrey
J
Jin
Ying-Tai
YT
Lin
Jin-Ching
JC
D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D036022:Capsid Proteins / Q000276:immunology; D004279:DNA, Viral / Q000097:blood*; D018572:Disease-Free Survival; D020031:Epstein-Barr Virus Infections / Q000276:immunology; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods*; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009303:Nasopharyngeal Neoplasms / Q000276:immunology / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011379:Prognosis
D000914:Antibodies, Viral; D000956:Antigens, Viral; D015415:Biomarkers; D036022:Capsid Proteins; D004279:DNA, Viral; C041788:Epstein-Barr viral capsid antigen; D007070:Immunoglobulin A; D007074:Immunoglobulin G