The transmission of a lymphomagenic agent(s) from the bone marrow of irradiated mice to thymic target cells has been demonstrated by: (a) the induction of T cell lymphomas in nonirradiated thymic grafts implanted in irradiated, Thy-l-congenic mice, (b) the induction of T cell lymphomas of host origin in mice infused with bone marrow from irradiated, Thy-l-congenic donors. The latter procedure a...

Mantle cell lymphoma is an aggressive type of B-cell non-Hodgkin's lymphoma that originates from small to medium sized lymphocytes located in the mantle zone of the lymph node. The gastrointestinal tract is the predominant site of extranodal involvement in the form of multiple lymphomatous polyposis. Multiple lymphomatous polyposis due to mantle cell lymphoma presenting with intussusception is ...

AIMS To determine levels of expression of Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) in benign and malignant tissues harbouring EBV in relation to EBNA1 promoter usage. METHODS Expression of EBNA1 was investigated by means of immunohistochemistry using a mixture of two EBNA1 specific monoclonal antibodies, 1H4-1 and 2B4-1. The presence of EBV was detected by EBER1/2 RNA in situ hybrid...

Antigen presentation by tumor cells in the context of Human Leukocyte Antigen (HLA) is generally considered to be a prerequisite for effective immune checkpoint inhibitor therapy. We evaluated cell surface HLA class I, HLA class II and cytoplasmic HLA-DM staining by immunohistochemistry (IHC) in 389 classical Hodgkin lymphomas (cHL), 22 nodular lymphocyte predominant Hodgkin lymphomas (NLPHL), ...

The translocation t(2;5)(p23;q35), discovered in CD30+ anaplastic large cell (ALC) lymphomas, creates a potentially oncogenic fusion gene, part of which is contributed by a novel tyrosine kinase, ALK. Absence of ALK expression from normal hematolymphoid cells provides a basis for the morphologic assessment of t(2;5). The distribution of the t(2;5) in ALC lymphomas and Hodgkin's disease (HD), as...

Multiple classifications of lymphomas are available. Generally, distinctions are made to identify low, intermediate, and high-risk groups. Histopathologic differentiation is at times difficult. The revised European-American lymphoma classification (REAL) uses histology, clusters of differentiation markers, histochemistry, and cytogenetics for definitive identification. This work reviews the kar...

T-cell non-Hodgkin's lymphomas are a heterogeneous group of diseases that differ markedly in terms of their clinical behavior and prognosis. In recently developed classification systems, the sites of initial disease presentation assume a more prominent role in subgroup delineation. CD26, a structure with an integral role in human T-cell function that serves as the binding protein to adenosine d...

Based on the results of histological and immunohistochemical observations of a large number of peripheral T cell lymphomas from China, England, Germany and Japan, histological and cytological morphology were correlated with immunophenotype, aetiological association with HTLV-1, and clinical behaviour to produce a working classification of the T cell lymphomas. This classification, based mainly ...

Marginal zone lymphomas of all types (nodal, splenic, and extranodal mucosa-associated lymphoid tissue [MALT]) may show plasmacytic differentiation. Distinguishing marginal zone lymphomas from other small B-cell lymphomas with plasmacytic differentiation, especially lymphoplasmacytic lymphoma, or from plasma cell neoplasms may be challenging. Marginal zone lymphomas with plasmacytic differentia...