Objective: To evaluate the value of combined assays of serum EBNA1-IgA and EA-IgG for serological diagnosis of nasopharyngeal carcinoma (NPC). Methods: The serum EBNA1-IgA and EA-IgG were tested by use of ELISA for 56 patients with NPC and 58 healthy adults. The sensitivity, specificity, positive predictive value, accuracy rate and odds ratio of the 2 tests used singly or in combination were compared with each other. Results: The sensitivity of EBNA1-IgA test (91.09%) was higher than that (87.50%) of EA-IgG test. The specificity of EA-IgG test (87.93%) was higher than that (84.48%) of EBNA1-IgA test. The combined usage of EBNA1-IgA and EA-IgG could enhance the specificity (94.83%), predictive value of a positive test (0.9375), likelihood ratio of a positive test (15.5435) and odds ratio (75.0) for serological diagnosis of NPC. Forty-five NPC patients showed positivity to EBNA1-IgA and EA-IgG concurrently. A positive EA-IgG reaction was demonstrated in 4 out of 5 NPC patients with negative EBNA1-IgA result and a positive EBNA1-IgA reaction in 6 out of 7 NPC patients with negative EA-IgG result as well. Conclusion: Though high sensitivity and specificity could be obtained by EBNA1-IgA and EA-IgG test, respectively, the combined use of these 2 tests is able to enhancing the reliability of serological diagnosis of NPC. The majority of NPC patients showed positivity to ENBA1-IgA and EA-IgG concurrently. There is a complementary effect through using EBNA1-IgA and EA-IgG for serological diagnosis of NPC.
Objectives To investigate the immunophenotypes of primary nasopharyngeal non-Hodgkin lymphoma (NPL) and their relationship to Epstein-Barr virus (EBV) infection.Methods The clinical data and biopsies of 73 patients with NPL were collected in Guangzhou. In situ hybridization was performed to detect the EBV-encoded small non-polyadenylated nuclear RNAs (EBERs) on biopsy slides. Immunohistochemistry was used to classify the immunophenotypes of NPL and detect EBV antigen expression. Results Forty-four (60.27%) of the 73 NPLs were of B cell lineage (CD79α+/CD3-/CD56-) while the 29 others (39.73%) were of non-B cell lineage. Seventy-three NPLs could be classified into 3 major immunophenotypes: B cell (CD79α+/CD3-/CD56-, 44 cases), peripheral T cell (CD79α-/CD3+/CD56-,22) and NK/T cell (CD79α-/CD3+/CD56+, 7). The percentages of EBV infection differed among the 3 major immunophenotypes (B cell: 11.36%, 5/44; peripheral T cell: 81.82%, 18/22; NK/T cell: 100%, 7/7). Both CD56-positive and CD56-negative immunophenotypes could further be divided into 4 subtypes: CD8-/CD4-,CD8+/CD4-, CD8-/CD4+ and CD8+/CD4+. All the CD8-/CD4- NPLs with CD56-positivity (7) or CD56-negativity (2) were infected with EBV. The neoplastic cells of a nasopharyngeal Burkitt’s lymphoma expressed EBV nuclear antigen 1 (EBNA1) and EBV RNA (EBERs) only. In the other 29 EBV-infected NPLs, most of the lymphoma cells harboring EBV also expressed EBNA1 and EBERs; 21 of the 29 NPLs had a considerable number of neoplastic cells expressing latent membrane protein 1 (LMP1) (21/29, 72.41%) and 23 of 29 NPLs expressed latent membrane protein 2A (LMP2A) (23/29, 79.31%). A few lymphoma cells in 17 (17/29, 58.62%), 23 (23/29, 79.31%) and 22 NPLs (22/29, 75.86%) expressed Zta (Bam HI Z transactivator), viral capsid antigen (VCA) and membrane antigen (MA), respectively.Conclusions The prevalence ratio of the 3 immunophenotypes, namely, B cell, peripheral T cell and NK/T cell lymphoma, is about 6∶3∶1. However, the EBV infection ratio is reversed, 1∶8∶1
