Prevalence of Epstein-Barr virus associated with nasal lymphoma in patients attending the regional hospital of Valdivia, Chile, between 1987 and 2005.

Epstein-Barr virus (EBV) is a ubiquitous herpes virus with a widespread infection in the world's adult population. EBV has been associated with human malignancies, mainly the nasal type NK/T cell lymphoma. The disease is more frequent in Asian than in Western countries. However, there are few studies from Latin American countries. The aim of this study was to determine the prevalence of EBV in patients with nasal lymphomas diagnosed in the Regional Hospital of Valdivia, southern Chile, during 1987-2005. Immunohistochemistry was done on paraffin sections using anti-CD3epsilon, anti-CD20, and anti-CD56. The presence of small ribonucleic acids (RNAs) of EBV was detected in paraffin sections by in situ hybridization using oligonucleotides targeting EBV-encoded small RNAs. The present study revealed a prevalence of 27.7% of Hodgkin's lymphomas and 72.3% of non-Hodgkin's lymphomas. From the latter group, there was a prevalence of 2.9% (10 cases) of nasal lymphoma. From these 10 cases, 6 (60%) were NK/T cell lymphomas, nasal type; 1 case (10%) was a T-cell phenotype; and 3 cases (30%) were B-cell phenotype. The prevalence was higher than reports from Western countries, but lower than the reports from Asian countries. These results agreed with previous reports suggesting that EBV is strongly associated with T lymphomas. This study contributes new epidemiological data on EBV in Chile.