Extranodal Malignant Lymphoma of the Upper Aerodigestive Tract: Prevalence of Epstien-Barr Virus (EBV) Infection in King Chulalongkorn Memorial Hospital
Thamathorn Assanasen MD*, Pongsak Wannakrairot MD*, Somboon Keelawat MD*, Preecha Ruangvejvorachai BSc*, Nootchanat Pramprayoon BSc*
Affiliation : * Department of Pathology, Faculty of Medicine, Chulalongkorn University
Background : High frequency of Epstein-Barr virus (EBV) in the normal mucosa of the upper aerodigestive
tract suggests that it may serve as a reservoir for the virus. Malignant lymphomas arising in this site may be
associated with EBV.
Objectives : To determine the prevalence of EBV infection in extranodal malignant lymphomas of the upper
aerodigestive tract.
Setting : King Chulalongkorn Memorial Hospital, Thailand.
Design : Descriptive study.
Patients: 42 Thai patients who presented between 1998 and 2003.
Materials and Methods : The expression of EBV mRNAs (EBERs) of malignant lymphoma was studied by means
of in situ hybridization in formalin-fixed, paraffin-embedded specimens.
Results : The recruited subjects were 26 males and 16 females, and their age ranged from 3 to 85 years with the
mean of 51.43 years, in 4 of them human immune deficiency virus (HIV) infection was documented. Ten of 42
cases (23.81%) expressed EBER transcripts and were extranodal NK/T-cell lymphomas, nasal type (7 cases),
plasmablastic lymphomas (2 cases) and diffuse large B-cell lymphoma (1 case). Three of 4 cases (75%) of
known HIV-seropositive cases were EBV-positive (2 plasmablastic lymphomas and 1 diffuse large B-cell
lymphoma).
Conclusion : In the upper aerodigestive tract, EBV was present in some but not all malignant lymphoma. It was
associated with extranodal NK/T-cell lymphoma, nasal type and B-cell lymphoma arising in HIV-infected
patients, but it was not found in B-cell lymphoma arising in immunocompetent patients.
Keywords : Epstein-Barr virus, EBV, EBER, Lymphoma, HIV, Upper aerodigestive tract, Extranodal, In situ hybridization, Bangkok, Thai, Thailand
