The WHO classification explains various special types of DLBCL, and DLBCLs harboring EBV in patients older than 50?years are termed EBV-positive DLBCL of the elderly (EBV-DLBCL of the elderly) as a new category.2,3 The EBV-DLBCL of the elderly category accounts for 8C10% of all DLBCL in Asian countries,4 but 5% in Western countries.5,6 EpsteinCBarr virus is the most common gamma herpes virus, and it has infected more than 90% of all adults. elderly) as a new category.2,3 The EBV-DLBCL of the elderly category accounts for 8C10% of all DLBCL in Asian countries,4 but 5% in Western countries.5,6 EpsteinCBarr computer virus is the most common gamma herpes virus, and it has infected more than 90% of all adults. Most people are infected subclinically in childhood and maintain a latent contamination throughout their life. During the process of contamination, EBV attaches Tafamidis (Fx1006A) to B cells through the binding of viral gp350 protein to CD21 on the surface of B cells. Then, gp42 on EBV interacts with MHC class II molecules and triggers fusion with the host membrane.7 The EBV Tafamidis (Fx1006A) is reactivated by various stimuli. EpsteinCBarr virus-infected B cells are usually controlled by EBV-specific T cells, but they become uncontrolled when the host is usually immunodeficient. B cells infected with EBV sometimes become lymphoblastoid cell lines and obtain an unlimited ability to proliferate. Lymphoblastoid cell lines cause some lymphoid malignancies, including Burkitt lymphoma, extranodal natural killer/T-cell lymphoma, aggressive natural killer leukemia/lymphoma, angioimmunoblastic T-cell lymphoma, Hodgkin’s lymphoma, immunodeficiency-associated lymphoproliferative disorders, and some DLBCLs.8 The standard treatment for DLBCL before the rituximab era was chemotherapy combined with CHOP. Since the introduction of rituximab into the clinic, R-CHOP has become the standard treatment for CD20-positive DLBCL.9,10 The outcome of DLBCL patients is improved with R-CHOP, but the impact on the prognosis of EBV-positive DLBCL patients remains controversial.11C15 We investigated the clinical features of patients with EBV-positive DLBCL and showed that the outcome of elderly patients with EBV-positive DLBCL treated with R-CHOP was still worse than other groups in this study. Materials and Methods Patients We reviewed the medical records of 289 patients who received a diagnosis of DLBCL at Tokai University Hospital (Isehara, Japan) and who were treated there and at affiliated hospitals between January 2007 and December 2011. Among 289 patients, 29 patients were excluded because no paraffin-embedded samples were available. Therefore, 260 cases were examined for the presence of EBV using formalin-fixed paraffin-embedded tissue sections. A suitably constituted Ethics Committee of our institution approved the protocol for this research project, and the work was carried out according to this protocol. Our study conformed to the provisions of the Declaration of Helsinki in 1995. EpsteinCBarr virus-encoded RNA hybridization and IHC EpsteinCBarr virus-encoded RNA hybridization was carried out using a fluorescein-conjugated EBER oligonucleotide probe and the purified IgG fraction of a mouse monoclonal anti-fluorescein antibody (Leica, Newcastle, UK). For IHC, mouse mAbs against CD3, CD5, CD10, CD15, CD20, CD79a, BCL-2, BCL-6, and MUM-1 (Novocastra, Newcastle upon Tyne, UK), and CD30 (Clone CON6D; Spanish National Cancer Research Centre (CNIO), Madrid, Spain) were used as primary antibodies. Detection of signals for EBER-ISH and IHC was carried out using the Leica BOND-MAX fully automatic IHC system with the BOND Polymer Refine detection kit according to the manufacturer’s instructions using BOND Epitope Retrieval Answer for 20?min for antigen retrieval (DS9800 and AR9640; Leica Microsystems, Tokyo, SCA12 Japan). For EBER-ISH-positive cases, LMP-1 (Novocastra) and EBNA-2 antibody (Novocastra) were examined with IHC. When more than 30% of large-sized cells were positive, the case was deemed EBV-positive. The DLBCL subtypes of GCB or non-GCB were categorized using CD10, BCL-6, and MUM-1 according to Hans’ algorithm.16 Cases that were unavailable for BCL-6 were categorized using CD10 and MUM-1 according to Chang’s algorithm.17 EpsteinCBarr computer virus latency was classified as: latency I, LMP-1(?) EBNA-2(?); latency II, LMP-1(+) EBNA-2(?); and latency III, LMP-1(+) EBNA-2(+). Clinical characteristics and statistical methods Comparisons of characteristics between EBV-positive and EBV-negative cases were examined Tafamidis (Fx1006A) with Fisher’s exact test or the non-parametric MannCWhitney 17.8%, respectively; hybridization; EBNA, EpsteinCBarr computer virus nuclear antigen antibody; EPOCH, rituximab, etoposide, doxorubicin, vincristine, cyclophosphamide, Tafamidis (Fx1006A) prednisolone; F, female; GCB, germinal center B cell; H, high; HI, high intermediate; IL2R, interleukin 2 receptor; IPI, international prognostic.
