July 29, 2024 – A breakthrough in medical testing technology now makes it possible to screen for colon cancer with just an easy blood test, promising a more accessible and fewer invasive method for early detection of the disease.
The FDA on Monday approved the test called Shield, which might accurately detect tumors within the colon or rectum in about 87% of cases when the cancer is in a treatable early stage. The approval was announced Monday from the test's manufacturer, Guardant Health, and comes just months after the promise Results of clinical studies published in The New England Journal of Medicine.
Colon cancer is one of the common cancers diagnosed within the United States annually and is a number one reason behind cancer death. The disease is treatable in its early stages, but about one in three people don't attend regular screenings, which should begin at age 45.
The simplicity of a blood test could increase the likelihood that individuals can be screened for the disease and ultimately survive. Other primary screening options include stool tests or a colonoscopy. The 5-year survival rate for colon cancer is 64%.
While the Shield test could be very accurate at detecting DNA shed by tumors in treatable stages of colon cancer, it was not as effective at detecting precancerous areas of tissue which can be normally removed after detection.
In their press release, Guardant Health officials said they expect the test to be covered by Medicare. The out-of-pocket cost for people whose insurance doesn't cover the test has not yet been announced. The test is anticipated to be available next week. The New York Times reported.
If an individual's Shield test is positive, further tests can be done to verify the result. Studies have shown that Shield has a false positive rate of 10%.
“I went for a routine checkup and my doctor asked me when I had my last colonoscopy,” said John Gormly, a 77-year-old businessman from Newport Beach, California, based on a Guardant Health press release. “I said it was a long time ago, so he offered to do the Shield blood test. A few days later, the result was positive, so he referred me for a colonoscopy. It turned out I had stage II colon cancer. The tumor was removed and I recovered very quickly. Thank God I had that blood test done.”