Based on morphology and phenotype, these cases would be regarded as DLBCLs, NOS, but the identification of genetic rearrangements of MYC, BCL2 and BCL6 by FISH analysis allows one to separate this category of aggressive lymphomas with a poorer clinical outcome with standard R-CHOP and clinical consideration for intensified chemotherapeutic strategies. This evidence concerns the gene BCL6 and lymphoma.