Nuclear staining for NOTCH2 is uncommon in BN2 DLBCLs, whereas nuclear staining for NOTCH1 is common in NOTCH1-mutated N1 DLBCLs. IHC was performed on a cohort of 314 DLBCLs. (A-B) Frequency and prevalence of NICD2 staining. (C-D) Frequency and prevalence of staining with an antibody that recognizes total NOTCH2. (E) NOTCH2 messenger RNA (mRNA) expression (variance stabilizing transformation [VST]-adjusted transcripts per kilobase million [TPM]) in BN2 DLBCL vs non-BN2 DLBCL cases (**P < .01). (F-G) Frequency and prevalence of NICD1 staining. (H-I) Representative images showing weak and limited NICD2 staining in DLBCL. (J) Example of DLBCL with diffuse membranous staining but absent nuclear staining for total NOTCH2. (K) Example of NOTCH1-mutated DLBCL with strong nuclear staining for NICD1. Images H-I were acquired using a MoticEasyScan Pro digital slide scanner (×40 magnification, standard mode; see https://moticeasyscan.com/product/moticeasyscan-pro/ for additional specifications) and Motic VM 3.0–Motic Digital Slide Assistant software (version 1.0.7.61b). All work was performed at room temperature in ambient air conditions. Fluorochromes were not required. Images were cropped using Adobe Photoshop Elements (version 14.0).