PDCD1 and diffuse large B-cell lymphoma: Targeted therapies that use antibodies against programmed cell death 1 (PD‐1) and its ligand (PD‐L1) have recently shown great promise in treating various malignancies, including relapsed or refractory DLBCL.16, 17 Overexpression of PD‐L1 on either DLBCL cells or tumor‐infiltrating immune cells has been associated with tumor cells that harbor EBV.18 Additionally, clinical trial studies have reported that the immune microenvironment of tumors generally correlates with the response rate to anti‐PD‐1/PD‐L1 therapies.19