The most commonly reported all‐grade hematological laboratory abnormality was anemia (88.9% [cHL anti‐PD‐1/PD‐L1 naïve], 58.3% [cHL anti‐PD‐1/PD‐L1 progressors], 100% [DLBCL and PTCL]). Here, CD274 is linked to anemia.