Analysis of Epstein—Barr virus in localized nasopharyngeal carcinoma tumors

Background. An f variant of Epstein‐Barr virus (EBV) appears associated with nasopharyngeal carcinoma (NPC) in Southern Chinese. Early diagnosis of the tumor allows the detection of some localized tumors. Methods. A polymerase chain reaction (PCR) assay for genotyping EBV was used to evaluate the presence of the virus in NPC biopsies of local tumors of eight Chinese patients. Results. The f variant was detected in the nasopharynx of seven of eight patients. The f variant was present in equal frequency in the “normal” and tumor regions. Conclusions. Examination of localized NPC tumors by the PCR genotyping assay revealed EBV was present on the tumor side of the nasopharynx in greater quantities than the “normal” side in seven of eight patients studied. Concurrent infection with both the prototype F and f variant was observed in two of the eight patients investigated.