Once confirmation of a hematolymphoid origin is established with CD45, the ideal IHC lymphoma work up for DLBCL includes CD3, CD20, CD5, CD10, bcl-2, bcl-6, MUM1, cyclin D1, CD30, Ki-67, and Epstein-Barr virus-encoded RNA (EBER) ISH. This evidence concerns the gene BCL6 and lymphoma.