High cancer mortality rates are mostly attributable to late diagnosis. That's because late-stage cancers that have already spread through the body are harder to treat. Cancer researchers are looking for ways to make earlier diagnoses, which could allow more successful treatment and improve patient survival rates.
So, what if early cancer detection was only a blood draw away? When there is a tumor present in the body, it can release certain proteins and DNA into the bloodstream. The detection of tumor-derived components, such as circulating tumor DNA (ctDNA) in the blood – using a technique known as liquid biopsy – seems to have the potential to complement standard screening techniques, improving early cancer detection and patient survival.
Now, a study recently published in Science examined the utility of liquid biopsy tests to check for several types of cancer at once. They gave their test, which detects genetic mutations and cancer-specific protein markers in blood, to nearly 10,000 women without any history or symptoms of cancer.
Participants with an initial positive blood test, meaning that they had detectable ctDNA mutations or increased levels of specific proteins, underwent a second blood draw to confirm the findings. Then, those with two positive results underwent PET-CT imaging to locate the cancer in their bodies.
Overall, oncologists diagnosed a total of 26 participants with cancer through these liquid biopsies. Some also underwent curative surgery. Remember, none of the participants had symptoms, so they previously had no idea that there was cancer present. These promising findings reveal that non-invasive blood tests could complement current cancer screening methods, doubling the rate of cancer detection and improving patient survival.