Detection of Epstein-Barr virus IgA/EA antibody for diagnosis of nasopharyngeal carcinoma by immunoautoradiography.

An immunoautoradiographic method was used for the detection of EB virus IgA/EA antibody in sera from NPC patients and other control groups. Ninety-six percent of NPC patients had IgA/EA antibody with a high titer of GMT. The positive rates of IgA/EA antibody in patients with malignant tumours other than NPC and in normal individuals were only 4% and 0%, respectively. Eleven patients histologically diagnosed as having a chronic inflammation and who showed positive for IgA/EA antibody by immunoautoradiography were rebiopsied; six of them were discovered to have squamous cell carcinoma. Fourteen NPC patients had no IgA/EA antibody detected by immunofluorescence and immunoenzymatic testing, but 11 and six of them had IgA/VCA and IgA/EA antibodies detected by immunoautoradiography, respectively. These data indicate that the immunoautoradiographic method is more sensitive than either the immunofluorescence or immunoenzymatic test for the detection of IgA/EA antibody, and can be used for the detection of NPC in the early stages of development.