 "cancer blood test")
Researchers have developed a non-invasive blood test that can screen eight common types of cancer long before symptoms appear.
Johns Hopkins Kimmel Cancer Center researchers said the test, called CancerSEEK is a unique non-invasive, multi-analyte test that simultaneously evaluates levels of eight cancer proteins and the presence of cancer gene mutations from circulating DNA in the blood.
The blood test might help to identify the location of the cancer.
Senior author Nickolas Papadopoulos said, "The use of a combination of selected biomarkers for early detection has the potential to change the way we screen for cancer and is based on the same rationale for using combinations of drugs to treat cancers."
They pointed out that this molecular test is solely aimed at cancer screening and, therefore, is different from other molecular tests.
The study involved 1,005 patients whose cancer -- already pre-diagnosed based on their symptoms -- was detected with an accuracy rate of about 70 percent overall.
Cancers of ovary, liver, stomach, pancreas, esophagus, colorectum, lung or breast were detected.
In 83 percent of cases, the test was even able to narrow down where the cancer was anatomically located.
The test is non-invasive and based on combined analysis of DNA mutations in 16 cancer genes as well as the levels of 10 circulating protein bio-markers.
For the five cancers that have no screening tests--ovarian, liver, stomach, pancreatic and esophageal cancers--sensitivity ranged from 69 percent to 98 percent.
The test was used on 812 healthy controls and produced only seven false-positive results.
They envision that the CancerSEEK test will eventually cost less than USD 500.
Although the current test does not pick up every cancer, it identifies many cancers that would likely otherwise go undetected.
The findings appear online in the Science journal.
