FcRL4 has positive expression in different proportions in mucosa-associated lymphoid tissue (MALT) lymphoma, DLBCL, DLBCL not otherwise specified (DLBCL-NOS), central nervous system (CNS) DLBCL, primary mediastinal large B-cell lymphoma (PMBL), and B-ALL/acute lymphoblastic lymphoma (LBL) [57], but its expression is up-regulated in MZL, CLL, and FL [51,58]. This evidence concerns the gene FCRL4 and diffuse large B-cell lymphoma.