A New $500 Blood Test Could Detect Cancer Before Symptoms Develop

An international team of researchers have developed a new test that screens for multiple types of cancer using only a blood sample.

The research published today in Science and led by scientists at Johns Hopkins School of Medicine in Baltimore describes a new test called CancerSEEK, which simultaneously looks for the presence of eight different types of cancer, including lung, breast and colorectal cancers, which are together responsible for more than 60 percent of cancer deaths in the U.S.

The researchers took blood samples from 1,005 people with one of the eight different cancer types, finding that CancerSEEK was able to reliably identify the tumors in 70% cases. The success rates ranged from an impressive 98% in people with ovarian tumors to only 33% in people with breast tumors.

However, the researchers are positive about the potential impact of the test. "If we are going to make progress in early cancer detection, we have to begin looking at it in a more realistic way, recognizing that no test will detect all cancers,” said Bert Vogelstein, M.D., Professor of Oncology at Johns Hopkins School of Medicine.

The scientists also used CancerSEEK on 812 healthy people with no history of cancer to make sure the test only picked up genuine cancers. Only seven of the 812 healthy people tested were flagged as positive using CancerSEEK, with the researchers noting that they couldn't be certain whether these seven individuals were true false positives or indeed had early-stage cancer with no symptoms.

The rate of false positives reported here is far lower than with conventional screening tests for specific cancers, such as mammography with a 10% false positive rate and colon cancer screening with variable rates of false-positives depending on the test used. Additionally, the proposed cost of CancerSEEK is $500, less than most currently available screens for single cancer types, making it an appealing prospect for individuals and insurers alike.