NFKB1 and diffuse large B-cell lymphoma: Germinal center‐derived B‐cell lymphomas have been defined (DLBCL, FL, and BL) based on histopathology and gene expression profiles.7, 8, 9, 10 DLBCL has been further classified into the GCB‐ and ABC‐DLBCL subtypes based on gene expression.9 An additional primary mediastinal subtype of DLBCL tends to occur in younger individuals with a bias toward females, and features strong NF‐κB signaling signatures.56 However, in the genome‐sequencing era it has become evident that these diseases are far more intricate.