Tracking Clonal Evolution of EGFR-Mutated Non-Small Cell Lung Cancer Through Liquid Biopsy: Management of C797S Acquired Mutation.

•Plasma NGS can track the clonal evolution of EGFR-mutated NSCLCs.•C797S mutation is one of the most common mechanisms of acquired resistance to osimertinib.•First generation can target C797S mutants, albeit responses are usually transient.•Novel therapeutic strategies are eagerly awaited for overcoming C797S mutation.