Shield Blood Test for Colon Cancer Screening Available at Coronado Health

By Coronado Health Direct Primary Care

Coronado Health Direct Primary Care is excited to announce a better alternative to Cologuard for colorectal cancer screening—Shield. Developed by Guardant Health, Shield is an FDA‑approved blood test that detects colorectal cancer (CRC)‑derived cell‑free DNA in the bloodstream for average‑risk individuals aged forty‑five and older. This innovative test is designed to reduce barriers to screening, improve adherence, and help detect more cancers at an earlier stage. Read on to learn who should get screened for colon cancer, why screening matters, and how Shield compares to existing options.

Why colon cancer screening matters

Colorectal cancer is the second leading cause of cancer‑related death in the United States, claiming over fifty‑three thousand lives annually. The American Cancer Society estimates that more than one hundred fifty thousand new CRC cases will be diagnosed in 2024. Thankfully, when colon cancer is detected early, the five‑year relative survival rate reaches 91 percent, while it plummets to just 14 percent once the cancer spreads to distant organs.

Despite these statistics, only about 59 percent of eligible adults in the U.S. complete colorectal cancer screening. That leaves more than 50 million individuals without up‑to‑date screening, resulting in a deadly gap. Many decline colonoscopy because it can be invasive, time consuming, and requires preparation. Others dislike the process of handling stool samples for tests like Cologuard or FIT (fecal immunochemical test) Verywell Health. Screening is most effective when people actually complete it. As noted by Dr Howard Hochster, the best screening test is the one that gets done. 

Who should get colon cancer screening

General guidelines

Health bodies such as the U.S. Preventive Services Task Force and the American Cancer Society recommend that individuals aged forty‑five and older at average risk for colorectal cancer undergo regular screening FDA Access Data. The typical screening options include:

• Colonoscopy every ten years
  
• Stool‑based tests such as FIT every year
  
• Stool DNA tests like Cologuard every three years
  

Average‑risk individuals

Average‑risk adults are those who:

• Have no personal or family history of colorectal cancer
  
• Do not have inflammatory bowel disease or genetic cancer syndromes
  
• Are not experiencing symptoms such as bleeding, abdominal pain, or changes in bowel habits.
  

Shield is approved for these average‑risk individuals aged forty‑five or older.

Who may need different screening

Other groups are considered higher risk and should follow a different screening plan:

• Personal history of CRC or polyps
  
• Inflammatory bowel disease such as ulcerative colitis or Crohn disease
  
• Family history of CRC or hereditary cancer syndromes
  
• Symptoms suggestive of CRC
  

Shield should not be used for these higher‑risk individuals. They may require diagnostic or surveillance colonoscopies instead.

What is Shield and how it works

Shield is a qualitative blood test that looks for cancer-associated fragments of cell‑free DNA (cfDNA) released into the bloodstream from colorectal tumors. Shield can be ordered during a routine primary care visit, with no need for preparation, fasting, or collecting stool samples. Early data from the randomized ECLIPSE trial of over twenty thousand people validated Shield’s performance.

Shield versus Cologuard and other options

Comparing sensitivities

• Colonoscopy: considered the gold standard, with highest sensitivity for both cancer and precancer
  
• Cologuard (stool DNA): 92 to 95 percent sensitivity
  
• Shield: 83 percent sensitivity for cancer, comparable to stool tests
  
• FIT: around 74 percent sensitivity
  
• Epi proColon (other blood test): about 50 percent sensitivity
  

Comfort and convenience

Shield offers clear advantages in comfort and convenience:

• No bowel prep needed
  
• No dietary restrictions
  
• No handling of stool
  
• Easily done during a routine blood draw
  
• Encourages higher adherence for those reluctant to undergo colonoscopy or stool tests
  

Limitations of Shield

Shield has lower sensitivity for early‑stage cancers and precancerous adenomas:

• 55‑65 percent detection of stage I cancer
  
• Only 13 percent detection of advanced adenomas
  

That means it cannot replace colonoscopy when prevention is the primary goal. Polyps are best detected and removed during colonoscopy. Shield is best considered complementary to colonoscopy: a more acceptable screening option for those avoiding traditional methods. But a positive result must be followed by colonoscopy.

Coverage and access

Shield is FDA approved as a primary CRC screening test for individuals aged forty‑five and older at average risk. It meets U.S. Centers for Medicare & Medicaid Services coverage criteria.

• Medicare Fee‑for‑Service: shield is covered at zero out‑of‑pocket
  
• Medicare Advantage: copay or deductible may apply
  
• Veterans Affairs & TRICARE: covered
  
• Commercial insurance: insurers are expected to include Shield due to FDA approval

How Coronado Health Direct Primary Care integrates Shield

At Coronado Health, we want to make colon cancer screening as accessible, comfortable, and effective as possible:

1. Offer Shield at routine visits – simple blood draw during regular check‑ups
   
2. Identify ideal candidates – average‑risk adults age forty‑five and older
   
3. Provide education – explain how Shield works, benefits, and limitations
   
4. Facilitate follow‑up – ensure that patients with positive Shield results get timely colonoscopy
   
5. Track adherence – our data team monitors who completes screening and follows through
   

By integrating Shield, we help overcome the adherence gap and detect more cancers early—possibly saving lives.

Is Shield right for you?

Shield should be considered by individuals who:

• Are forty‑five years of age or older
  
• Are at average risk for colorectal cancer
  
• Prefer blood testing over colonoscopy or stool sampling
  
• Want a test with high sensitivity for cancer (83%) and excellent specificity (90%)
  

Shield may not be the best choice if you:

• Have a family or personal history of CRC or polyps
  
• Have inflammatory bowel disease or hereditary cancer risk
  
• Are experiencing symptoms like bleeding or abdominal pain
  
• Want maximal prevention through polyp detection
  

In these cases, colonoscopy remains the most effective option.

Next steps and recommendations

• Age forty‑five? Talk to us about Shield during your next visit
  
• Not up‑to‑date on screening? Shield offers a practical first step
  
• Positive Shield result? We will arrange a colonoscopy follow‑up
  
• Not eligible for Shield? We will guide you to appropriate screening like colonoscopy or Cologuard
  

Regular colorectal cancer screening is crucial. Shield provides a convenient, patient‑friendly option without sacrificing accuracy for cancer detection.