Study Finds Liquid Biopsies More Effective than Traditional Biopsies in Detecting Cancer Drug Resistance

Liquid biopsies based on blood samples do a better job than traditional biopsies in analyzing both the genetic diversity of the patient’s cancer and how tumors evolve drug resistance at the molecular level. That is the finding of a new study from a group of researchers from, among other institutions, Harvard, the Broad Institute of MIT and Massachusetts General Hospital (MGH). What’s At Stake Like other organisms, tumors evolve to survive adverse environmental changes. A tumor that shrinks in response to one drug may undergo evolutionary change enabling it to fend off the cancer drug and reemerge. Being able to rapidly detect cancer drug resistance and evolutionary patterns is thus crucial to finding a new drug that the tumor will still respond to. Cancer diagnosis has traditionally relied on tissue biopsies as the principal source of this information. But in addition to being invasive, tissue biopsies provide a glimpse of only one location in a single tumor, which limits their effectiveness to the extent tumor cells may be genetically distinct from one another. Liquid biopsies, by contrast, are performed on patient blood samples containing DNA from tumors, i.e., circulating tumor DNA or ctDNA, which can be isolated and analyzed. But […]