Atezolizumab for first-line treatment of metastatic nonsquamous non-small cell lung cancer: what makes the difference?

The landing of immune checkpoint inhibitors (CKI) in the landscape of the primary treatment for non-small cell lung cancer (NSCLC) patients has been surely irrepressible, but burdened by a large selection limit, constituted by the percentage threshold of programmed death-ligand 1 (PD-L1) expression (1).