It is well known that Epstein-Bars virus (EBV) has been linked to nasopharyngeal carcinoma (NPC) on the basis of epidemiological

serological and molecular biological data. Determination of titres of antibodies to EBV in serum-EBV-VCA-IgA

EBV - EA - IgA

and assay of EBV-DNA in tissue of patients with polymerase chain reaction (PCR) has been used for diagnosis of NPC. This paper evaluated the value of both assay mentioned above in the use for diganosis of NPC.85 patients were investigated.For each patient

determination of EBV- VCA-IgA(Ⅰ)

EBV-EA-IgA (Ⅱ) in serum

EBV-DNA assay with PCR (Ⅲ) and histo-pathological examination (Ⅳ) of biopsy of nasopharyngeal tissue were performed with double-blind studies. 57 patients with NPC were confirmed by histo-pathopathological examination

and 28 patients were proven histo-logically non-NPC and served as control. Of 57 NPC

the positive rate of (Ⅰ). (Ⅱ ) or (Ⅲ) were 66.7%

21.1%

80.7% respectivelly

and (Ⅰ )+(Ⅱ)

(Ⅰ)+(Ⅲ)

(Ⅱ)+(Ⅲ)

or(Ⅰ)+(Ⅱ)+(Ⅲ) were 21.1%

56. 1%

19.3%

19.3% (P<0. 005).For 28 control cases

the negative rate of (Ⅰ ). (Ⅱ) or (Ⅲ)were 75%

100%

100% respectivelly

and(Ⅰ)+(Ⅱ)

(Ⅰ )+(Ⅲ)

or (Ⅰ ) +(Ⅱ)+(Ⅲ)were 71.4%

71.4%

71.4% (P<0.005). Our results suggested that assay of EBV-DNA with PCR have best sensitivity (positive rate of NPC is high) and specificity (negative rate of control is high)for diagnosis of NPC and could be used in early diagnosis of NPC.