Detection of occult nasopharyngeal primary tumours by means of in situ hybridization.

Detection of nasopharyngeal carcinoma primaries in patients presenting with neck node metastases may sometimes demand considerable efforts. By using the 'in situ hybridization' technique, we manage to identify the Epstein-Barr virus in neck metastases secondary to nasopharyngeal carcinomas. We propose that such identification in neck node metastases where the primary lesion is unknown indicates a nasopharyngeal primary.