Melanoma Associated Antigen 1 (MUM1)

One hundred forty-nine of 163 DLBCLs could then be classified into GCB group (pattern A), activated GCB group (pattern B) and activated non-GCB group (pattern C) according to the expression of CD10, Bcl-6, MUM1, and CD138.  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.  Such distinction is made possible using the immunohistochemical expression of CD10, Bcl-6 and MUM1.  Immunohistochemical stains for CD10, Bcl-6 and MUM1 were performed on 18 cases of primary testicular lymphoma of diffuse large B-cell type.