Detecting cancer by monitoring circulating tumor DNA

DNA that is shed by dead tumor cells into the blood, termed circulating tumor DNA (ctDNA), is a rich resource that could potentially be used for cancer diagnostics and monitoring. A new study describes a sequencing-based method that improves upon the sensitivity and specificity achieved by past techniques for detecting ctDNA and that can be used for monitoring of disease burden in patients with non–small-cell lung cancer (pages 548–554).