DLBCL, gray zone lymphomas, and Hodgkin lymphomas. MLBCL and T-cell/hisotcyte–rich large B-cell lymphoma (T/HRBCL) are considered “gray zone lymphomas,” which share characteristics of large B-cell lymphomas and Hodgkin lymphomas (cHL and NLPHL, respectively), including increased host inflammatory response. The similarities among these entities points to a group of tumors defined, and possibly driven, by their interaction with the host microenvironment. Images provided by J. Kutok, Department of Pathology, Brigham and Women's Hospital, Boston, MA. The samples were analyzed using an Olympus BX41 microscope equipped with 40×/0.75 and 20×/0.50 Olympus UPlanFL objective lenses (Olympus, Melville, NY). Pictures were taken using Olympus QColor3, and were analyzed with QCapture 2.60 software (QImaging, Burnaby, BC, Canada). Adobe Photoshop 6.0 was used to process images (Adobe, San Jose, CA).