PDCD1 and neoplasm: Although PD‐1 and/or CTLA4 blockade can be accompanied by the development of immune‐related toxicities, antibodies targeting these receptors have nonetheless shown marked therapeutic efficacy in various tumours, including melanomas, non‐small‐cell lung carcinomas, renal cancers and Hodgkin lymphoma (Pardoll, 2012; Ribas & Wolchok, 2018).