Detection of epstein‐barr virus DNA in formalin‐fixed paraffin‐embedded tissue of nasopharyngeal carcinoma using polymerase chain reaction and in situ hybridization

The polymerase chain reaction method for amplification of DNA in formalin-fixed, paraffin-embedded tissue sections was used to detect Epstein-Barr virus DNA in nasopharyngeal carcinomas from Japanese patients. Thirty-one cases of nasopharyngeal carcinoma and 8 cases of lymph node metastasis of nasopharyngeal carcinoma were studied. Detection rates of Epstein-Barr virus in various types of nasopharyngeal carcinoma according to the World Health Organization classification were as follows: 10 of 10 undifferentiated carcinomas, 8 of 13 nonkeratinizing carcinomas, and 5 of 7 keratinizing carcinomas. Eight lymph node metastases, for which the primary was positive for Epstein-Barr virus, also contained Epstein-Barr virus DNA. By in situ hybridization using a biotinylated Epstein-Barr virus probe, it was clearly demonstrated that Epstein-Barr virus DNA was localized in the nuclei of the neoplastic cells. The clinical features of nasopharyngeal carcinoma with or without Epstein-Barr virus were not different. These results demonstrate that nasopharyngeal carcinoma in Japanese patients is closely associated with Epstein-Barr virus infection, similar to nasopharyngeal carcinoma of other endemic and nonendemic areas.