Guardant Health

Breakthrough cancer test

1 minute read

A new era of cancer detection is under way, using simple blood tests. In 2022, Guardant Health introduced Shield, one of the first blood-based tests to screen for colorectal cancer. While it wouldn’t replace colonoscopies, the gold standard for detection, the relative ease of the breakthrough test can significantly increase the number of people who are diagnosed earlier with colorectal cancer. It’s the second highest cause of cancer death in the U.S. and diagnosis rates have been rising for decades among people younger than 50. Earlier this year, new clinical-trial results showed the Shield test is 83% accurate in identifying patients with cancer overall, and 100% accurate for cancer at stages II and higher. Guardant expects Shield to be the first FDA approved blood test for colorectal cancer screening that Medicare could cover, which would make it available to more patients.

Correction, May 30
The original version of this story misstated the status of Guardant's blood test. It is not the first blood test for colorectal cancer, but it is expected to be the first to get FDA approval and Medicare reimbursement.

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