Because diffuse large B-cell lymphoma and other high-grade B-cell lymphoma can look identical morphologically to “double-hit” lymphoma, at a minimum MYC FISH must be obtained in every case (see Figure 1 for an example of a case that has similar morphology to diffuse large B-cell lymphoma, NOS on various slide stain preparations, but ended up having both MYC and BCL2 rearrangements). This evidence concerns the gene MYC and B-cell non-Hodgkin lymphoma.