[1][2] Like traditional biopsy, this type of technique is mainly used as a diagnostic and monitoring tool for diseases such as cancer, with the added benefit of being largely non-invasive.
Liquid biopsies may also be used to validate the efficiency of a cancer treatment drug by taking multiple samples in the span of a few weeks.
[4] Liquid biopsy refers to the molecular analysis in biological fluids of nucleic acids, subcellular structures, especially exosomes, and, in the context of cancer, circulating tumor cells.
[27][28] Cancer mutations in ctDNA mirror those found in traditional tumor biopsies, which allows them to be used as molecular biomarkers to track the disease.
Scientists can purify and analyze ctDNA using next-generation sequencing (NGS) or PCR-based methods such as digital PCR.