Epstein‐Barr virus in lymphoproliferative diseases in the sino‐nasal region: Close association with CD56+ immunophenotype and polymorphic‐reticulosis morphology

Association between Epstein‐Barr virus (EBV) and nasal T‐cell lymphoma (NTL) has been demonstrated. NTL has 2 types of histologic figures: one is ordinary non‐Hodgkin's lymphoma (NHL) with monomorphous proliferation, and the other is polymorphic‐reticulosis (PR) morphology. The presence of the EBV genome and its sub‐types (A and B) were examined on paraffin‐embedded specimens from 36 cases of sino‐nasal lymphomas (SNL) collected from Seoul, Republic of Korea, where the frequency of NTL is high. Patients' ages ranged from 2 to 74 years (median 54 years) with a male‐to‐female ratio of 2.5:1. Immunophenotypically, 8 cases were B‐cell type, 11 were T‐cell type with CD56−, 14 were CD56+ type, and 3 were null‐cell type. Five of 11 cases with ordinary NHL of T‐cell type and 9 of 14 cases with PR were CD56+. The EBV genome was found by polymerase chain reaction (PCR) and in the tumor cells by in situ hybridization (ISH) in 1 of 4 B‐cell type (25%), 5 of 10 T‐cell type (50%), 11 of 13 CD56+ type (85%), and in both of null‐cell type (100%). Of 16 cases with PR morphology, 15 (94%) were positive for the EBV genome. All of the 5 NTLs of ordinary NHL with CD56− were negative for EBV. Concerning the sub‐type of BV, 16 cases had type A, while none had type‐B EBV. These findings suggest that NTL comprises 2 groups: EBV‐positive NTLs are CD56+ and/or histologically PR, and EBV‐negative NTLs are CD56− and histologically ordinary NHL. The current results on Korean patients, together with earlier studies on Japanese and Malaysian patients, have shown the predominance of type‐A EBV in sino‐nasal lymphoma in Asia. © 1997 Wiley‐Liss, Inc.