Diagnostic significance of latent membrane protein 1 (LMP-1), EMA, CD45, CD20 and CD3 in Epstein-Barr Virus-associated Nasopharyngeal Carcinoma

Background: Nasopharyngeal carcinoma (NPC) is a squamous cell carcinoma which differ from other head and neck cancers and linked to the Epstein Barr virus (EBV) and its encoded oncoproteins, such as EBNA1 and LMP1.These viral oncogenes have been found to be an important factor in its pathogenesis. Objectives: To diagnose NPC and differentiate it from lymphoma, also to assess the expression pattern of LMP1 in the different histological types of NPC in a sample of the Egyptian population and to introduce serologic methods for screening and early detection of NPC. Results: Eighty-eight trans-nasal biopsies were examined. Carcinoma of the nasopharynx was detected in 79 of them. Of NPC patients 74/79 (93.6 %) showed positive test against IgA/ VCA. Late Membrane Protein was detected in 37/43(74 %) of cases of NPC tumor. Using histopathology as the gold standard for NPC, the sensitivity and specificity was 84% and 86% respectively with highly significant (p = 0.018). Epithelial membrane antigen was detected in 32/43 (64 %) NPC biopsies, the sensitivity and specificity was 72 % and 86 % respectively (p= 0.018). CD45 was positive in all 50 biopsies in the background leukocytes and negative in the tumor cells. Conclusion; Type III undifferentiated carcinoma is the commonest type of NPC. The antibodies to EBV-VCA IgA are of diagnostic value in early detection and are recommended for NPC screening at the population level.