LYMPHOEPITHELIAL CARCINOMA OF THE SALIVARY-GLAND - IN-SITU DETECTION OF EPSTEIN-BARR-VIRUS

Aim-To examine the role of Epstein-Barr virus (EBV) in lymphoepithelia l carcinoma of the salivary gland in Hong Kong Chinese. Methods-Ten ca ses of lymphoepithelial carcinoma of the salivary gland (eight parotid and two submandibular) were examined. In situ hybridisation was used to localise EBER RNA, immunohistochemical methods to detect expression of latent membrane protein 1 (LMP-1) in EBV positive tumours, and Sou thern blot analysis to examine the clonality of EBV in the two cases w here frozen tissue was available. Results-None of the cases had a hist ory of Sjogren's syndrome or histological evidence of a benign lymphoe pithelial lesion. The IgA antibody titre against EBV viral capsid anti gen was elevated in four cases. All cases were EBV positive by in situ hybridisation, with a strong uniform positive signal in the epithelia l cells, and all cases expressed LMP-1. Southern blot analysis reveale d that the clonal episomal form of the virus was present. Two of the t hree female patients in this series also developed carcinoma of cenix. One of these carcinomas had histological features of a lymphoepitheli oma-like carcinoma but was EBV negative. Conclusions-A consistent asso ciation between EBV and lymphoepithelial carcinoma of the salivary gla nd was found, The presence of the virus in a clonal episomal form, and the expression of LMP-1 viral oncoprotein is further evidence of the role of EBV in the oncogenesis of this tumour.