Abstract
Until recently, the prognosis and treatment of patients with advanced-stage squamous cell lung cancers have been limited. An improvement in the understanding of the role of the immune system in tumor immunosurveillance has led to the development of the programmed death-1 (PD-1) immune checkpoint inhibitor nivolumab (Opdivo). Nivolumab is the first PD-1 inhibitor approved for the treatment of advanced-stage squamous cell non-small-cell lung cancer following platinum-based chemotherapy. In the key Phase III trial CHECKMATE 017, a better overall survival and progression-free survival were seen in patients treated with second-line nivolumab compared with docetaxel. Programmed death ligand-1 (PD-L1) expression did not predict for outcome. In addition, nivolumab had better safety and tolerability, and led to better patient reported outcomes. Further research on the role of PD-L1 expression as a predictive biomarker should be performed, and other biomarkers that can predict the efficacy of PD-1/PD-L1 inhibitors should also be pursued. Further studies on the combination treatment are ongoing to determine the optimal role of nivolumab as monotherapy or nivolumab with other agents in non-small-cell lung cancer.