DNA in Blood Monitors Treatment of Metastatic Cancer

American Cancer Society research grantee develops a new, low-cost way of measuring DNA in blood—with faster results.

The Challenge

Metastatic cancer refers to a cancer that has spread from where it started to a new part of the body—in a process called metastasis. Many of these cancers can be hard to treat because cancer cells change during the process of spreading and treatments that worked before may no longer work. Because of this, a key part of treating metastatic cancer is to continually evaluate how well a treatment is working so an ineffective treatment can be stopped and other options can be offered.

The Research

To measure a treatment’s effect, tests have been developed to look for high levels of tumor DNA circulating in the bloodstream—called ctDNA, for circulating free DNA.

Recent ACS grantee Hanlee P. Ji, MD, has developed a highly sensitive, potentially customizable, and practical approach for detecting ctDNA in the blood of patients with several types of metastatic cancer, including breast, colorectal, lung, and melanoma. The approach is called digital PCR, or dPCR (digital polymerase chain reaction). Hanlee’s recently published results from a pilot study show that dPCR may be as effective as other methods used to measure ctDNA. Plus, it’s low-cost, with results available in a matter of hours.

Why It Matters

While the studies are still in their early phases, Hanlee’s research supports the use of ctDNA monitoring with dPCR testing along with other tests or alone. So far, comparisons of this new approach to existing blood tests and imaging options are encouraging. More investigation could lead to improved monitoring of treatment response in patients whose cancer has spread.

See the study.