PDCD1 and neoplasm: Hence, in addition to the radiological response associated with ICIs, reflecting their anti-proliferative effects, anti-PD-1/PD-L1 drugs have useful properties in controlling hormone hypersecretion, particularly in aggressive or metastatic ACTH- and PRL-secreting PitNETs, which is often accompanied by tumour mass reduction [4,36,37,41,43].