PDCD1 and non-small cell lung carcinoma: In the phase III CheckMate 057 trial evaluating nivolumab versus docetaxel in previously treated NSCLC, the objective response rate to PD-1 blockade in the LKB1-mutant subgroup was only 7.4%, compared with over 35% in the LKB1 wild-type subgroup (P < 0.001).