PDCD1 and non-small cell lung carcinoma: The Checkmate 159 trial was the first study to use PD-1 inhibitor as neoadjuvant regimen for resectable NSCLC, and it showed that, after two doses of nivolumab preoperatively, 45% of resected tumors (9/20) had a major pathological remission (MPR), and 10% of patients (2/20) even achieved a pathological complete response (pCR) (12).