ASCO has updated its guideline on systemic therapy for stage IV non-small-cell lung cancer (NSCLC).

Regarding first-line treatment of non-squamous cell carcinoma (SCC) or SCC (without positive markers), if the patient has:

• High programmed death ligand 1 (PD-L1) expression, use pembrolizumab alone.
• Low PD-L1 expression, offer standard chemotherapy.

Regarding second-line treatment in patients who received first-line chemotherapy without prior immune checkpoint therapy, if the tumor:

• Is positive for PD-L1 expression, use single-agent nivolumab, pembrolizumab, or atezolizumab.
• Has negative or unknown PD-L1 expression, use nivolumab or atezolizumab.

For patients:

• Who received a prior first-line immune checkpoint inhibitor, offer standard chemotherapy.
• Who cannot receive immune checkpoint inhibitor after chemotherapy, use docetaxel.
• With nonsquamous NSCLC, use pemetrexed.
• With a sensitizing epidermal growth factor receptor (EGFR) mutation, disease progression after first-line EGFR tyrosine kinase inhibitor therapy, and T790M mutation, use osimertinib (or chemotherapy in absence of T790M mutation).
• With ROS1 gene rearrangement, offer crizotinib if it was not used previously, or chemotherapy if it was.