Vol. 93 No.5 May 2000
Clinical and Epstein-Barr Virus Aspects of Nasal NK/T Cell Lymphomas
Yasuaki Harabuchi
The author reviewed clinical, phenotypic, genotypic, and Epstein-Barr virus(EBV)-findings of 44 patients with nasal lymphomas. In phenotypic analyses, 35 patients were classified as having NK/T cell (CD56-positive) type, 5 as having T-cell type, and the remaining 4 as having B-cell type. Twenty-six (74%) patients with NK/T cell lymphomas had ulcerative/destructive lesions, but 9 NK/T lymphoma patients did not. EBV-encoded small unclear early region (EBER) transcripts were indentified in 35 patients. Monoclonal EBV genome and EBV-encoded unclear antigen (EBNA)-1 were also detected in all EBER-positive cases tested. The NK/T cell lymphoma patients without ulcerative/destructive lesions had favorable prognoses, but the lymphoma patients with ulcerative/destructive lesions that were clinically lethal midline granulomas had a higher incidence of systemic symptoms, decreased PBL counts, and high serum LDH levels, and showed significantly poorer progonoses. These results suggest that patients with nasal NK/T lymphoma, in which EBV may play a role of lymphomagenesis, may be classified into two distinct subgroups according to involvement of ulcerative/destructive lesions.
Key words: Epstein-Barr virus, nasal, NK cell, lymphoma, lethal midline granuloma