Premium
Laboratory markers of tumor burden in nasopharyngeal carcinoma: A comparison of viral load and serologic tests for Epstein‐Barr virus
Author(s) -
Fan Hongxin,
Nicholls John,
Chua Daniel,
Chan K.H.,
Sham Jonathan,
Lee Shuko,
Gulley Margaret L.
Publication year - 2004
Publication title -
international journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.475
H-Index - 234
eISSN - 1097-0215
pISSN - 0020-7136
DOI - 10.1002/ijc.20520
Subject(s) - nasopharyngeal carcinoma , serology , viral load , titer , virus , medicine , epstein–barr virus , immunology , antigen , virology , antibody , radiation therapy
Abstract Epstein‐Barr virus (EBV) is present within the tumor cells of most cases of nasopharyngeal carcinoma (NPC). Recent studies suggest that tumor burden is proportional to the level of EBV DNA in blood and that rapid blood testing can be used to guide therapeutic intervention. The relative utility of viral load vs. serology has been insufficiently studied. In our study, EBV viral load was measured by quantitative PCR using either real‐time or end‐point detection systems in serum samples from 124 NPC patients (93 pretreatment, 13 relapsed, 18 in remission) and 40 controls. Serologic titers against EBV early antigen were measured in the same serum samples. EBV DNA was detectable in 64 of 93 untreated NPC patients (69%; mean viral load 11,211 copies/ml), 11 of 13 relapsed NPC patients (85%; mean 53,039 copies/ml) and 0 of 18 remission patients. EBV DNA was detectable in only 1 of 40 non‐NPC controls (3%). In 34 instances where paired plasma and serum samples were available for testing, both were effective sample types, and there was no significant difference between end‐point and real‐time methods for measuring viral load. Early antigen (EA) IgA and IgG titers were elevated in most NPC patients regardless of whether their disease was active or in remission. EBV viral load was more informative than was EA serology for distinguishing remission from relapsed disease. EBV DNA measurement appears to be a noninvasive way to monitor tumor burden after therapy. © 2004 Wiley‐Liss, Inc.