The wide uptake of liquid biopsy diagnostics in the care of advanced cancer patients highlights the desire for improved access to tumor allowing accurate tumor genotyping (1). Genotyping of plasma cfDNA is now routine for detection of EGFR driver mutations at diagnosis of NSCLC, or for detection of the EGFR T790M mutation after TKI resistance, and is an emerging approach for the detection of other drivers (HER2 or BRAF mutations, ALK or ROS1 fusions…) (2) or the estimation of tumor mutation burden (TMB) (3). However, the most sensitive plasma genotyping platforms still have a sensitivity of only 70%-80%, such that a negative result requires tissue biopsy confirmation.