Epstein-Barr Virus Infection as Significant Predisposing Factor and Post-Radiotherapy Prognostic Indicator among Libyan Patients with Nasopharyngeal Cancer

Abstract

Background and Objectives: Libya is one of the North African countries which constitute an area of nasopharyngeal carcinoma endemicty, particularly at the north part of Libya as compared to its south portion. Although from the clinical as well as histopathological presentation, there is no uniquely specific pattern of appearance, but there is high deficiency in the data that confirm the possible predisposing factors which may play a role in the development of this common variety of head and neck cancer at this country, and whether these factors affecting the patients response to treatment. Therefore this study was conducted to elucidate the suggestion of the role of Epstein-Barr Virus (EBV) in the risk of nasopharyngeal cancer at Libyan population; the results were correlated with the radiotherapy response and the improvement in the post-therapy prognostic value. Patients and Methods: Sixteen patients aged 9-80 years presented at ENT department -Althowra central teaching hospital-elbyda-Libya at period from September- 2005 up to January-2014 with variable patterns of clinical presentation suggestive nasopharyngeal carcinoma. All patients were evaluated radio- logically as well as endoscopically, the diagnosis was confirmed by the biopsy and further histo-pathological assessment. For all patients the serological elucidation for IgG and IgM anti-EBV antibodies was done, and the results were correlated with the age of the incidence, sex of the incidence, the pattern of clinical presentation, the pattern of histo-pathological presentation, the response to the radiotherapy, the rate of the recurrence, and five years survival. Results: 88% of the patients showed significant increase of serum IgG against Viral Capsid Antigen (VCA) of EBV. 83% of the cases presented with cervical masses and unilateral otitis media with effusion. 86% of cases showed lympho-epithelioma as histo-pathological pattern. On the other hand among all patients, those patients with lympho-epithelioma showed significant response to the concomitant radio- chemotherapy (100%) with high survival rate exceed five years. Conclusion: The EBV infection can be considered as one of main predisposing factors of nasopharyngeal carcinoma at Libyan population. As it was noted from this presenting study that the induction of the cancer by EBV is mainly due to chronic infection rather than acute infection and this was confirmed by significant elevation of serum IgG rather than IgM. In addition it was postulated that the EBV infection most likely to be associated with lympho-epithelioma variety of histo-pathology rather than well-differentiated type, and as it was elucidated via this study that the association of the cancer with EBV infection increased the sensitivity of the tumor to concomitant radio-chemotherpy, thus this will improve the five years survival after the treatment.