CD20 expression by IHC and FCM of representative “dim” CD20 and “bright” CD20 DLBCL samples. (A) Representative hematoxylin and eosin stain of a “bright” CD20 DLBCL. (B) CD20 protein expression by IHC of a “bright” CD20 DLBCL. (C) CD20 expression by flow cytometry of a “bright” CD20 DLBCL. (D) Representative hematoxylin and eosin stain of a “dim” CD20 DLBCL. (E) CD20 protein expression by IHC of a “dim” CD20 DLBCL. (F) CD20 expression by flow cytometry of a “dim” CD20 DLBCL. (A,B,D,E) Slides were viewed with a Nikon Eclipse E600 microscope (Nikon Canada, Mississauga, ON) at a magnification of 400×. Images were acquired using a Nikon Digital Camera DXM1200 (Nikon Canada) and were processed with Adobe Photoshop version 7.0 software (Adobe Systems, San Jose, CA).