These markers are the minimum to best classify a lymphoma as of B-phenotype (CD20+,CD3−), from germinal center origin (CD10+, bcl-6+, MUM1-) or non-germinal center origin (CD10−, bcl-6−/+, MUM1+), as a “double expressor” or not (bcl-2+ and c-myc+), as an EBV+ LBCL, and to exclude the diagnosis of blastoid or pleomorphic mantle cell lymphoma (CD5+ and cyclin D1+). This evidence concerns the gene BCL6 and mantle cell lymphoma.