Novel Epstein-Barr virus immunoglobulin G–based approach for the specific detection of nasopharyngeal carcinoma
Received 19 November 2008 published online 27 August 2009. Corrected Proof
Abstract
Purpose
This study was designed to find a reliable Epstein-Barr virus (EBV) immunoglobulin (Ig) G–based diagnostic/screening test for nasopharyngeal carcinoma (NPC) able to demarcate between the NPC-related seropositivity of EBV IgG antibodies and that of other head and neck cancer (HNCA) and control groups. The NPC-associated immunosuppression affects EBV IgA much more than IgG, leading to inconsistent detection of NPC using EBV IgA antibodies.
Materials and methods
One hundred twenty-two HNCA patients, 42 NPC, 66 laryngeal carcinoma, and 14 hypopharyngeal carcinoma and 3 groups of 100 control subjects were enrolled in this study. Enzyme-linked immunosorbent assay (ELISA) was used to find a specific cutoff value for the NPC-related seropositivity of EBV IgG antibodies.
Results
NPC group showed higher serum level of EBV IgG antibodies than control and other HNCA groups (P < .05). However, the traditional cutoff value, mean + 2 SDs of control subjects, failed to demarcate the seropositives of NPC patients from those of healthy population (P > .05). The new cutoff value, mean + 2 SDs of the seropositives group of control subjects who had already been grouped by the traditional cutoff value, proved successful. It succeeded to demarcate between the NPC-related EBV IgG seropositivity and that issued from the persistent, latent, or reactivated EBV infection in the population (P < .05). The sensitivity/specificity of NPC detection by the new cutoff-based ELISA kit, 76.19% and 86%, was close or higher than that of EBV IgA antibodies.
Conclusion
EBV IgG-based ELISA could be used for the diagnosis of NPC using a new cutoff threshold that excludes the population baseline of EBV IgG seropositivity.
aMicrobiology Research Department, University Putra Malaysia, Serdang, Malaysia
bInstitute of Bioscience, University Putra Malaysia, Serdang, Selangor Darul Ehsan, Malaysia
cFaculty of Food Science and Technology, University Putra Malaysia, Serdang, Malaysia
Corresponding author. Microbiology Research Department, University Putra Malaysia, 43400, UPM, Serdang, Malaysia. Tel.: +60 132580401.
ABSTRACT