Detection of Epstein - Barr virus DNA by PCR in Tissue Biopsies of Patients with Nasopharyngeal Carcinoma at the University of Maiduguri Teaching Hospital: Ten Years Retrospective Review

Abstract

Nasopharyngeal carcinoma (NPC) is an endemic disease in Southern China, with an nd incidence rate of 25 per 100,000, population. The  disease was ranked the 22 most common cancer in the world; however, in Nigeria, the cancer was said to be rare or possibly underreported. The neoplasm was found to be strongly associated with EBV infection as an aetiological agent. A dearth of publications  relating to the association of EBV and NPC in Nigeria prompted the need for this study. The study was a hospital-based retrospective  survey. Forty-one (n=41) archived tissue blocks from confirmed cases of NPC (2005-2014) were used; the DNAwas extracted using Qiagen.  The extracted DNAwas amplified using the conventional three steps with 129bp EBNA-1 primers. The results were then analysed  using SPSS version 23 and presented as simple frequencies and percentages in tables and pictures. There were 19,127 total biopsies  during the study period and 514(2.7%) were ENT cases. A total of 2,713(14.2%) were diagnosed with cancer and 261(9.6%) of these were  ENT malignancies out of which 41(15.7%) were NPC which made the inclusion criteria of the study. In the 41 NPC cases analyzed, the  male-to-female ratio was 6:1. The age range was 15-84 years and the mean age was 35.24 ± 2.7 SD. There were 31(75.6%) cases of Grade  2b NPC, 9(22%) cases of Grade 2a, and one case (2.4%) of Grade 1. Twenty-six (63.4%) of the samples were positive for EBV-DNA and  15(36.6%) were negative cases. The highest positive cases of EBV-DNAwere found within the age range of 15-40 years and were  predominantly Grade 2b NPC. The present study shows a high frequency of EBV DNAassociated with nasopharyngeal carcinoma mostly in  Grade III (2b). The age groups commonly affected were the second to fourth decades. In view of this, there is a need to establish a  baseline serum EBV-DNA in the normal population in our community, this can assist in the early detection and prompt management of  patients with NPC.