PDCD1 and neoplasm: Therefore, blockade of PD1/PD-L1 using monoclonal antibodies (e.g., Nivolumab (Opdivo®) and Pembrolizumab (Keytruda®)) provides an attractive way to restore the body’s immune system to attack tumour cells, which has been suggested as a treatment for NSCLC, particularly in PD1 high-expressing tumours [106,107,108,109].