Blood biopsies for cancer

Many cancers are diseases of old (or at least middle) age, and as the population ages, it is becoming even more widespread. Half of us are now predicted to develop cancer during our lifetimes and, globally, one person is diagnosed with a form of the disease every one or two seconds. When we get detection and diagnosis right, more and more types of cancer will be turned from killer diseases into curable or at least manageable ones. The concept of a liquid biopsy for cancer – sampling body fluids, usually blood, and analysing their components as a proxy for sampling the tumour itself – was introduced in 2010. But as yet there are no blood biopsies for cancer in clinical use outside trials.