The future of blood tests in cancer treatment

Interviewer: Dr. Isaac Garcia-Murillas, thank you for joining us today. You and your colleagues at The Institute of Cancer Research have recently developed an ultrasensitive liquid biopsy that can detect breast cancer relapse significantly earlier compared to other detection methods. My first question for you would be, can you please explain what is a liquid biopsy? Dr. Garcia-Murillas: Thank you for the invite, first of all. It's a pleasure to be with you today. What is a liquid biopsy? That's an excellent question to start with. Liquid biopsy, akin to normal biopsy, is a way to detect tumor DNA, but in this case, non-invasively. There is no need to take what we call a traditional biopsy. A liquid biopsy could be any biofluid in the body that has remnants of tumor DNA. There is an association, currently, between the term "liquid biopsy" and blood draw, and potentially, it's the most advanced of them all. But any other, as I said, biofluid can be used. That is, spinal fluid and urine, for example, and saliva, so this is a way to non-invasively detect a tumor using biofluids from the body. Interviewer: What are the current approaches for detection of circulating tumor DNA in the blood? Dr. Garcia-Murillas: Currently, there are two main ways of detecting circulating tumor DNA, or ctDNA, in the blood. One of them uses digital PCR technology, and the second one uses next-generation sequencing. When we started with this around 2013/2014,