Presence of Epstein-Barr virus DNA in carcinomas of the palatine tonsil.

The presence of Epstein-Barr virus genetic material was demonstrated in thin sections of biopsy specimens in 6 of 7 carcinomas of human palatine tonsil by the in situ hybridization test. The biopsy specimens from 4 tonsillar carcinomas exhibited a strong positive reaction; two biopsy specimens were weakly positive. Two tumor-free biopsy specimens were negative. None of the thin sections reacted with 3H-labeled herpes simplex virus DNA probe.