'Liquid Biopsy' can Find Cancer DNA in Blood

A new blood test dubbed 'liquid biopsy' is set to revolutionize the way cancer is diagnosed and treated, as it could replace conventional tissue biopsy testing.

According to The New York Times, the new test looks for cancer DNA in a blood sample that acts as marker for several purposes. For now, researchers are using DNA's presence to learn if treatment given to the patient is working. A recent study National Cancer Institute (NCI) study also showed that the test can detect reoccurrence.

"Surveillance circulating tumor DNA identifies patients at risk of recurrence before clinical evidence of disease in most patients and results in a reduced disease burden at relapse. Interim circulating tumor DNA is a promising biomarker to identify patients at high risk of treatment failure," NCI study's authors wrote in the journal The Lancet Oncology.

Researchers at Sloan Kettering Cancer Center where the technique was put to use explained that cancer DNA is circulating in the system for only a brief while before it is metabolized. While they hailed the test, oncology experts said it needs more evaluation before it can be used in the wider clinical setting.

The endgame for the blood test would be early cancer detection. At present researchers are not sure how to link cancer DNA in blood with detection as some cancers may not develop into a disease and yet others may not need treatment until clinical symptoms appear, which may happen months or years after the test.