BCL6 and diffuse large B-cell lymphoma: Rather, when it is present by IHC in the absence of their rearrangement, detected by FISH, it can be classified as another entity of DLBCL called dual expresser (DE).2 The presence of MYC and BCL2 rearrangement is common in DH DLBCL, while rearrangement of BCL6 is rare.3 DH DLBCL is typically of germinal center B-cell origin, commonly referred to as GCB; DE DLBCL is typically of non–germinal center origin, non-GCB.