Dr Jean-François Martini (Pfizer Inc., USA) added another voice to the choir supporting the use of liquid biopsies, using circulating cell-free DNA to determine patient genotypes over the course of the PALOMA 3 trial [5], which assessed fulvestrant with either palbociclib or a placebo, and a separate first-in-human trial of lorlatinib for ALK+ non-small cell lung cancer (NSCLC) [6]. This evidence concerns the gene ALK and non-small cell lung carcinoma.