Can a blood test detect cancers before symptoms start?

April 04, 2018 | by Alexander Hantel, M.D.

Wouldn’t it be nice if there was one test that could tell you if cancer is in your future? Well, this possibility may be closer than you think — using only a blood sample.

Researchers at Johns Hopkins Kimmel Cancer Center have developed a single blood test that screens for eight common cancer types and helps identify the location of the cancer.

This new test, called CancerSEEK, looks for the presence of lung, breast, colorectal, esophageal, liver, ovarian, pancreatic and stomach cancers. These cancers account for more than 60 percent of cancer deaths in the U.S.

For five of the cancers covered by the test — including ovarian, liver, stomach, pancreatic and esophageal cancers — there are no other screening tests currently available.

Here’s how CancerSEEK works: The unique, noninvasive test measures circulating tumor DNA (ctDNA) from 16 genes as well as eight protein biomarkers and then uses machine-based learning to analyze the data. According to Johns Hopkins, circling tumor DNA mutations can be highly specific markers for cancer.

Researchers took blood samples from 1,005 people, with one of eight non-metastatic stages of different cancer types. They found that CancerSEEK was able to reliably identify tumors in 70 percent of cases.

CancerSEEK was also used on 812 healthy people with no history of cancer to make sure the test only picked up genuine cancers. The rate of false positives reported was far lower than with conventional screening tests for specific cancers.

Since this test is considered a screening tool, researchers believe the test should cost similar to other screening tools that are currently available. They envision that CancerSEEK will eventually cost less than $500 and be given to a patient when they visit their primary care provider for a routine check-up. Just as a patient would have their cholesterol tested, they could also get screened for different types of cancer.

Researchers are on the right track, but they still have a long way to go before this new type of blood test can be implemented. The next step in their research is to validate their findings by studying a larger scale of healthy individuals.

We know early detection is key to reducing cancer deaths and finding symptoms before they even start. That’s why it’s so important to follow your doctor’s recommendations for routine screenings, including mammograms, Pap tests and colonoscopies.

This research is an example of how cancer screenings are evolving, and how we are getting better at finding more cancers that would otherwise go undetected early rather than late.

Learn more about cancer care at Edward-Elmhurst Health.

What do you think about a blood test that detects cancer? Tell us in the below comments.

Related blogs:

How to do your part and not get cancer


7 ways to make this your summer of fitness

As the days lengthen and sunshine becomes a staple, it’s easy to let your fitness routine slip away.

Read More


Why cancer and trouble sleeping go hand-in-hand

If you’re undergoing cancer treatment, you may find yourself having trouble sleeping. Don’t worry — you are not alone.

Read More