Blood test detects common cancers


Researchers have developed a non-invasive blood test that can screen eight common types of cancer long before symptoms appear.

The test, called CancerSEEK, is a unique noninvasive, multianalyte test that simultaneously evaluates levels of eight cancer proteins and the presence of cancer gene mutations from circulating DNA in the blood.

Scientists are reporting progress on a blood test to detect many types of cancer at an early stage, including some of the most deadly ones that lack screening tools now.

The findings were published online by Science on January 18, 2018.

"We're very, very excited and see this as a first step", said Nickolas Papadopoulos, one of the Hopkins study leaders.

According to report, 70 percent success was recorded with the new test, but that cannot be used to draw a conclusion on the test as more and larger studies still need to be carried out on it in order to be sure if actually, it can help save the lives of cancer patients.

Known as a liquid biopsy, the test is distinctly different to a standard biopsy, where a needle is put into a solid tumour to confirm a cancer diagnosis. So patients in a real-life screening likely would have less advanced disease and might be more hard to test.Also, in a real-life scenario, even healthy patients who would be tested could have inflammatory or other diseases that could skew test results, which wasn't seen among the healthy patients in the study.The researchers have moved forward with a follow-up, five-year study to further evaluate the blood test, Papadopoulos said in a teleconference with reporters on Friday. "The proportion of common cancers - breast, lung, colorectal - detected is again not as high as other, rarer cancers". This can then indicate the presence of ovarian, liver, stomach, pancreatic, oesophageal, bowel, lung or breast cancers.

Also speaking on the breakthrough is Dr. Cristian Tomasetti who is also from Johns Hopkins.

Dr. Richard Schilsky, chief medical officer of the oncology society, said results are encouraging, but the test needs more study, especially to see if it gives too many false alarms.

To zero in on the analytes they included in their CancerSEEK test, the research team pulled data from more than three decades of cancer genetics research generated at their Ludwig Center at Johns Hopkins, where the first genetic blueprints for cancer were created, as well as data from many other institutions. But the test is still some years away from being used in the clinic. "The more DNA bases you assay, the more mutations you are capable of finding, but eventually you reach a point of diminishing returns", explains Cohen. For each of these tumour types there are now no screening tests available - blood based or otherwise. The result was a relatively small panel of highly selective DNA markers. It can be performed without even knowing a cancer is present, and therefore allow for early diagnosis and more chance of a cure. Earlier detection provides many ways to improve outcomes for patients. But it was only successful at detecting earliest stage 1 cancers about 40 percent of the time.

They envision that the CancerSEEK test will eventually cost less than Dollars 500.

Larger studies of the test are now under way.

Publication: Detection and localization of surgically resectable cancers with a multi-analyte blood test.