According to Prof. Olivier Michielin, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland, comments on two studies presented at ESMO 2019 providing new insights into the use of liquid biopsy in early detection. One study reported of a high sensitivity of a targeted methylation assay in detecting multiple types of tumours, while a second study provided supporting evidence in the use of liquid biopsy for early detection of disease progression and resistance in advanced non-small cell lung cancer (NSCLC).