Primary testicular diffuse large B-cell lymphomas have activated B-cell-like subtype characteristics.
Diffuse large B-cell lymphomas (DLBCLs) constitute a heterogeneous group of lymphomas in which germinal centre B-cell-like and activated B-cell-like subtypes can be discerned based on pathology, clinical presentation, and gene expression patterns. Testicular DLBCLs form an immune-privileged site-related subgroup of DLBCLs with an unfavourable prognosis. In the present study, cDNA microarray analysis, immunohistochemistry for CD10, Bcl6 and MUM1, and somatic hypermutation analysis of the immunoglobulin heavy chain gene rearrangements were used to determine the subtype of primary testicular DLBCL. Immunohistochemistry revealed 14/22 testicular DLBCLs with an activated B-cell-like immunophenotype and 8/22 with an ambiguous immunophenotype co-expressing CD10 and high levels of MUM1. cDNA microarray analysis of these 22 and four additional cases showed a uniform activated B-cell-like gene expression pattern for both immunophenotypes. Somatic hypermutation analysis of immunoglobulin heavy chain genes showed a very high mutation load in seven cases tested, but intraclonal heterogeneity was found at low level in only one of these cases. It is concluded that primary testicular DLBCLs have uniform activated B-cell-like subtype characteristics despite a number of cases showing an ambiguous immunophenotype.
Booman
M
M
Department of Pathology and Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. m.booman@path.umcg.nl
Douwes
J
J
Glas
A M
AM
de Jong
D
D
Schuuring
E
E
Kluin
P M
PM
D001402:B-Lymphocytes / Q000276:immunology*; D016000:Cluster Analysis; D018076:DNA, Complementary / Q000235:genetics; D004273:DNA, Neoplasm / Q000235:genetics; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics; D016130:Immunophenotyping; D050835:Interferon Regulatory Factors / Q000378:metabolism; D008213:Lymphocyte Activation; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D008297:Male; D009363:Neoplasm Proteins / Q000378:metabolism; D015260:Neprilysin / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D027041:Somatic Hypermutation, Immunoglobulin; D013736:Testicular Neoplasms / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D000099218:Interferon Regulatory Factor-4
D018076:DNA, Complementary; D004273:DNA, Neoplasm; D007135:Immunoglobulin Variable Region; D050835:Interferon Regulatory Factors; D009363:Neoplasm Proteins; D015260:Neprilysin; D000099218:Interferon Regulatory Factor-4