This Blood Test Detects Cancer In People Even Without Symptoms

Doctors may soon be able to detect cancer even before people start to experience symptoms of the disease. A new tool has been developed to identify different kinds of cancer through a single analysis of a person’s blood. 

Researchers at Johns Hopkins University said they are the first to show that a single approach could screen people for several types of cancer. The team has provided the blood test, called a liquid biopsy, to nearly 10,000 women who never showed cancer symptoms, CNN reported.

The new approach, described in the journal Science, appeared effective to identify 26 forms of cancer. Researchers also used a combination of PET and CT scans to confirm the presence of tumors. 

The team said the blood test even identified cancer types that doctors usually catch only after they have already spread. These diseases are known to have subtle symptoms in the early stages.

"They had no idea that they had cancer before the test was performed," Bert Vogelstein, lead researcher at Johns Hopkins, told CNN.

One of the hard to detect diseases identified by the blood test was ovarian cancer. Women commonly get diagnosed with the cancer in its deadly stages. 

Vogelstein said one of the participants was able to know she had ovarian cancer when it was still at stage 1. That provided her more options for treatment as it had not spread across her body. 

"Her five-year survival is predicted to be 91 percent," the researcher said. "If she had not been detected until there had already been metastases (spread), her predicted survival would have been 26 percent."

The blood test also helped the researchers detect lung cancer earlier in 9 women. This is another form of the disease known to be diagnosed only when it's too late. 

Researchers provided the participants with cancer treatments as part of the study. After 11 months, some of those that tested positive appeared cancer-free.

The team noted that the blood test still has limitations. But only 1 percent of the participants got a false positive, which means the test indicated they had cancer but the PET/CT scan did not find a tumor.

The Johns Hopkins team has already established a company called Thrive Earlier Detection to bring the cancer detecting blood test to the market. However, the tool is expected to take a few more years to be available. 

Researchers plan to conduct another trial with a larger population to confirm the accuracy of the blood test.

blood test A representation of a scientist conducting blood test in the lab. Pixabay

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