Sanjay Popat, BSc, MBBS, FRCP, PhD, The Royal Marsden NHS Foundation Trust, London, UK, outlines the findings of a study presented at ELCC 2021 which investigated the use circulating tumor (ct)DNA next-generation sequencing (NGS) in the UK for patients with advanced non-small cell lung cancer (NSCLC) in a real-world setting. The study reported that 167/184 patients who underwent ctDNA NGS had at least one genomic variant. 43% of these patients had a tier 1 variant, of which 29% were not identified in tissue. The study concluded that upfront use of ctDNA NGS should be routinely considered for patients with NSCLC. This video was recorded at the virtual European Lung Cancer Congress (ELCC) 2021.