Diagnostic value of Epstein-Barr viral serology in nasopharyngeal carcinoma

Although Epstein-Barr virus (EBV) IgA serology has been established as an effective marker for nasopharyngeal carcinoma (NPC), it remains unclear how useful or cost-effective it is as a screening test. This article is aimed at establishing how these tests could be used most effectively in the diagnosis of NPC in an otolaryngology outpatient clinic. A total of 111 consecutive patients with NPC and an equal number of control subjects were studied. Forty-seven patients with NPC had early (AJCC stages 1 and 2) and 64 had advanced (stages 3 and 4) disease. A positive early antigen (EA) serology result was found in 81.2% of NPC patients and in none of the controls. Negative EA and viral capsid antigen (VCA) serology results were present in 2.7% of NPC patients and in 46.8% of controls. Negative EA and positive VCA serology results were found in 30.0% of NPC patients with early disease, 7.8% of NPC patients with advanced disease, and 53.2% of controls. Given its high specificity, serology for EA is recommended as a clinically useful screening test. Serology for VCA, although highly sensitive, has an unacceptably high false-positive rate, and its cost-effectiveness as a universal screening test is questionable.