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Large and systematic studies of non-Hodgkin lymphoma (NHL) in the Far East (FE) with good comparative data are scarce in the literature. In this study, five expert hematopathologists classified 730 consecutive cases of newly-diagnosed NHL from four sites in the FE (excluding Japan) using the World Health Organization classification. The results were compared to 399 cases from North America (NA). We found a significantly higher male to female ratio in the FE compared to NA (1.7 versus 1.1; p < 0.05). The median ages of patients with low-grade (LG) and high-grade (HG) B-NHL in the FE (58 and 51 years, respectively) were significantly lower than in NA (64 and 68 years, respectively). The FE had a significantly lower relative frequency of B-NHL and a higher frequency of T-NHL (82 vs. 18 %) compared to NA (90.5 vs. 9.5 %). Among mature B cell lymphomas, the FE had a significantly higher relative frequency of HG B-NHL (54.8 %) and a lower frequency of LG B-NHL (27.2 %) than NA (34.3 and 56.1 %, respectively). Diffuse large B cell lymphoma was more common in the FE (49.4 %) compared to NA (29.3 %), whereas the relative frequency of follicular lymphoma was lower in the FE (9.4 %) compared to NA (33.6 %). Among T-NHL, nasal NK/T cell NHL was more frequent in the FE (5.2 %) compared to NA (0 %). Peripheral T cell lymphoma was also more common in the FE (9.1 %) than in NA (5.3 %). Further epidemiologic studies are needed to better understand the pathobiology of these differences. [ABSTRACT FROM AUTHOR]

Fifty-five consecutive cases of Hodgkin’s lymphoma (HL), collected between 1996 and 1998 from Cairo, Egypt, were histologically subtyped, phenotyped, and then studied for the presence of Epstein–Barr virus (EBV). We used immunohistochemical stains for EBV latent membrane protein 1 (LMP-1) and in situ hybridization stains for EBV-encoded small RNA (EBER-1) transcripts. Forty-five cases (82%) had classic HL (cHL), and ten cases (18%) had nodular lymphocyte predominant HL (NLPHL), with each group expressing its typical phenotype. LMP-1 stains were positive in 63% and 0% of cHL and NLPHL cases, respectively. EBER-positive Reed–Sternberg cells and variants were also present in 62% and 0% of each group, respectively. The cHL cases showed variable EBER positivity: nodular sclerosis, 58%; mixed cellularity, 100%; lymphocyte depletion, 100%; and unclassifiable, 67%. Our findings are similar to those from other developing countries and point towards a pathogenic role of EBV in cHL. [ABSTRACT FROM AUTHOR]

Anaplastic large-cell lymphoma is associated with a chromosomal translocation generating an oncogenic fusion protein: the nucleophosmin-anaplastic lymphoma kinase (NPM-ALK). We have generated several independent lines of human NPM-ALK transgenic mice using the haematopoietic cell-specific Vav promoter. Lymphomas develop in two transgenic lines in which the Vav promoter regulates NPM-ALK expression. The transgenic line with higher copy number displays an early-onset phenotype in which all mice succumb to aggressive lymph node tumours with intestinal involvement, whereas the second line displays late-onset tumour development in the spleen and/or liver. Lymphomas from both lines are phenotypically distinct and display B-lineage characteristics with aberrant coexpression of myeloid markers. The NPM-ALK kinase is active in primary tumour tissue and forms a multimeric complex with tyrosine-phosphorylated proteins, that is, Shc. Jun and ERK kinase activities in tumours are elevated by up to 30-fold and fivefold, respectively, in comparison with sIgM-stimulated primary B cells. The new transgenic models provide a system for investigating the oncogenic events mediated by NPM-ALK in situ and a physiologically relevant context for developing tyrosine kinase inhibitor therapies of potential use in the clinic.Oncogene (2003) 22, 7750-7761. doi:10.1038/sj.onc.1207048 [ABSTRACT FROM AUTHOR]