© National cancer InstituteScientists have discovered that dying tumor cells release small pieces of their DNA into the bloodstream. These pieces are called cell-free circulating tumor DNA (ctDNA).
Researchers say they have taken a big step towards developing a test that can tell people if they have cancer long before the first symptoms show up.
The blood test detected the majority of cancers in people with four of the biggest cancer killers: breast, colon, lung and ovarian cancer, the team at Johns Hopkins University said.
The
test is a long way from being used to screen for cancer, but the study shows a way to get there, the team reported in the journal
Science Translational Medicine.
"There is a lot of excitement about liquid biopsies, but most of that has been in late-stage cancer or in individuals where you already know what to look for," said Dr. Victor Velculescu, professor of oncology and pathology at the Johns Hopkins University Kimmel Cancer Center.
"The surprising result is that we can find a high fraction of early-stage patients having alterations in their blood," said Velculescu, who led the study team.
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