What Biomarkers to Test for in Non–Small Cell Lung Cancer?

Biomarker testing has become central to first-line decision-making in non–small cell lung cancer (NSCLC), with therapy selection increasingly guided by molecular profiling rather than histology alone. Current National Comprehensive Cancer Network and American Society of Clinical Oncology guidelines call for broad, next-generation sequencing–based testing in eligible patients with metastatic disease, alongside PD-L1, EGFR, and ALK testing in select early-stage patients being considered for neoadjuvant or adjuvant therapy. This slideshow reviews the biomarkers oncologists should be testing for in NSCLC, from established drivers like EGFR and ALK to newer additions such as MET exon 14 skipping mutations and HER2 alterations, along with guidance on when and how testing should be performed.