PDCD1 and lymphoma: The PD-1/PD-L1 axis also plays an important role for immune evasion of lymphomas [9], most notably in classical Hodgkin lymphoma (cHL) and primary mediastinal B-cell lymphoma (PMBCL), ICIs inducing remarkable response rates in patients with relapsed/refractory (r/r) disease, leading to their approved use in this setting [10–12].