NOW FDA APPROVED FOR COLON CANCER SCREENING

Medical questions

Frequently asked questions

  • The ECLIPSE clinical study validated Shield as a high-sensitivity blood test for colon cancer screening, with an 83% sensitivity for colon cancer and 90% specificity1
  • Sensitivity, or the true positive rate, is the ability of a test to detect those who truly have a condition. A true positive refers to those who have the condition and tested positive for the condition, i.e., if there are 100 people with colon cancer, Shield will correctly identify 83% of them
  • Specificity, or the true negative rate, is the ability of a test to exclude those who are truly free of a condition. A true negative refers to those who do not have the condition and tested negative for the condition,i.e., if there are 100 people without colon cancer or advanced adenoma, Shield will correctly identify 90% of them as not having colon cancer or advanced adenoma

In general, a person who is at average risk for colon cancer is an adult 45 years or older who does not have: 

  • Prior diagnosis of colorectal cancer, adenomatous polyps, or inflammatory bowel disease
  • A personal diagnosis or family history of colorectal cancer or known genetic disorders such as Lynch syndrome or familial adenomatous polyposis

It is best to ask your healthcare provider if you are at average risk for colon cancer

  • The Shield test is designed for colon cancer screening, and it can detect DNA shed by colon cancer. It is recommended that you follow up with your healthcare provider to see what test would be appropriate to provide you with information on specific tumor markers
  • No, Shield is not indicated for this use. However, Guardant Health has products that can be used for those purposes. If you would like more information about that, please visit https://guardanthealth.com 
  • Please contact your healthcare provider to help determine what test would be appropriate to provide you with that specific information

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Important Product Information

Intended Use

The Shield™ test is a qualitative, in vitro diagnostic test intended to detect colorectal cancer derived alterations in cell-free DNA from blood collected in the Guardant Shield Blood Collection Kit.
Shield is indicated for colorectal cancer screening in individuals at average risk for the disease, age 45 years or older. Patients with a positive result should be followed by colonoscopy. Shield is not a replacement for diagnostic colonoscopy or for surveillance colonoscopy in high-risk individuals. This test is performed at Guardant Health, Inc.

Precaution: Based on data from clinical studies, Shield has limited detection (55%-65%) of Stage I colorectal cancer and does not detect 87% of precancerous lesions. One out of 10 patients with a negative Shield result may have a precancer that would have been detected by a screening colonoscopy. Shield demonstrated high detection of Stage II, III, and IV colorectal cancer.

Limitations and Other Important Information: The Shield test is not indicated for patients that have personal history of colorectal cancer, adenomas, or other related cancers; or those who had a positive result on another colorectal cancer screening method within the last six months, have been diagnosed with a condition associated with high risk for colorectal cancer such as Inflammatory Bowel Disease (IBD), chronic ulcerative colitis (CUC), Crohn’s disease; or who have a family history of colorectal cancer, or certain hereditary syndromes. Providers should discuss the most appropriate screening test to use with patients depending on their medical history and individual circumstances. Shield may produce a false negative or false positive result. A false negative result may occur when the Shield test does not detect a colorectal tumor signal while a colonoscopy identifies a colorectal cancer. A negative result does not guarantee the absence of colorectal cancer or advanced adenoma, and patients should continue participating in colorectal cancer screening programs at the appropriate guideline-recommended intervals. A false positive result may occur when the Shield test generates a positive result while a colonoscopy will not find colorectal cancer or advanced adenoma.

Please read our Provider Brochure for complete product information about the Shield test including full safety information.

  1. Reference:
  2. Chung DC, Gray DM II, Singh H, et al. A cell-free DNA blood-based test for colorectal cancer screening. N Engl J Med. 2024;390(11):973-983.doi:10.1056/NAEJMoa2304714