May 01, 2021

Exciting potential for liquid biopsies

If a doctor suspects that you have cancer, a tumor biopsy — taking a sample of tissue or cells through an invasive procedure for analysis — can determine whether cancer is present and help guide treatment.

But researchers are now exploring ways to examine cancer-related material in your blood. This is known as a liquid biopsy. Cancer cells shed fragments of DNA — known as circulating tumor DNA (ctDNA) — into your bloodstream, and researchers are exploring ctDNA as a way to:

  • Plan treatment — Standard biopsies may not tell the whole story. Other tumors in the body — or even other areas of the same tumor — can vary genetically, for example. Because your blood collects ctDNA from all over your body, using ctDNA could help plan treatment using a more comprehensive picture of your cancer.
  • Monitor treatment — Tumors can change over time. However, going through multiple standard biopsy procedures can be difficult, with accompanying risks such as pain, bleeding and infection. In contrast, it’s easier to undergo multiple blood draws to examine ctDNA over time. And because the amount of ctDNA may change in proportion to the extent of disease, ctDNA could be used to measure how well a certain treatment is working.
  • Detect new or residual cancer — Liquid biopsies using ctDNA may be able to detect microscopic deposits of cancer that remain or develop despite treatment for early-stage disease, and they could potentially be...