FDA approves blood test to detect colon cancer
Last reviewed: 14.06.2024
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On Thursday, an advisory panel to the US Food and Drug Administration (FDA) recommended approval of a new blood test that can detect colon cancer.
The panel voted 7-2 that the benefits of Guardant Health's Shield test outweigh the risks of its use to diagnose colon cancer.
"The advisory committee's strong support for Shield's approval highlights the important role that the blood test option can play in improving [colon cancer] screening rates for those at average risk," Guardant co-chairman AmirAli Talasaz said in a company press release., announcing the voting results.
"Despite the importance of early detection of colorectal cancer, there are significant barriers that may prevent average-risk Americans from completing existing screening methods," added Talasaz. "Shield is effective at detecting cancer early, when it is most treatable. Providing people with this blood test, along with other non-invasive stool tests, could increase screening rates and potentially reduce the number of preventable deaths from [colon cancer]."
If the FDA approves the Shield test, it will be the second blood test to diagnose colon cancer in the United States: the first test, Epigenomics' Epi proColon, was approved in 2016.
Approximately 150,000 patients in the United States are diagnosed with colon cancer each year, and it is the second leading cause of cancer deaths in the country, causing more than 50,000 deaths per year, according to the American Cancer Society.
Colonoscopy is currently the gold standard for testing for colon cancer, but adherence to this method is low due to its invasiveness and complex preparation for the test. Other methods include stool tests such as Exact Sciences' Cologuard, but blood tests are considered more convenient, NBC News reported.
Members of the panel expressed concern that Guardant's test was not as accurate as colonoscopy, especially since Shield detected only 13% of precancerous tumors called advanced adenomas, NBC News reported. This issue was also raised by FDA staff in internal documents.
Guardant's application for approval was based on a study showing the test detected 83% of colon cancer cases, according to FDA documents.
"Shield is better than nothing, but I don't want to downplay the fact that this test may miss a lot of cancers," panel member Charity Morgan, a professor in the department of biostatistics at the University of Alabama, said during the panel meeting, NBC News reported. p>
The company expects the test will need to be repeated every one to three years, Guardant Health Chief Executive Victoria Raymond said during the meeting, but added that "colonoscopy should be the priority option," NBC News reported.