Nasopharyngeal carcinoma (NPC) has been linked to Epstein-Barr Virus (EBV) by seroepidemiological evidence and by the regular proof of EBV-DNA in the epithelial tumor cells. We have been able to study the serological parameters of 62 NPC patients of the local ENT-Clinic. All patients were kaukasians in contrast to a previous study by Henle et al. Our results emphasize the remarkable predominance of EBV-IgA antibodies to viral capsid antigen (VCA) and early antigen (EA) in NPC patients and prove the value of the test for the initial diagnosis of the disease. Follow-up studies with subsequent serological tests strongly suggest that this test is related to the stage of the disease. We have also found NPC-typical serological EBV-IgA titers in 3 lymphoepithelial carcinomas of the tonsil and the soft palate. Similar titers have been found in two cases of poorly differentiated carcinomas of the base of the tongue. All these tumors arise in the lymphoepithelial tissue of Waldeyer's ring. We conclude that possibly some carcinomas of Waldeyer's ring are similarly related to EBV as nasopharyngeal carcinomas are.