However, a high frequency of mutations involving this pathway has been reported in extranodal DLBCLs not arising in IP sites, such as intravascular large B-cell lymphomas (IVLBCLs), primary cutaneous lymphoma DLBCLs-leg-type (PC DLBCL-LT), vitreoretinal (PVRL), or primary breast DLBCLs, at variable frequency and mostly with concomitant CD79B mutations [47] (Figure 1). This evidence concerns the gene CD79B and incontinentia pigmenti.