Blood-Based Colon Cancer Screening Falls Short Without Follow-Up

According to a new study, patients often fail to follow through with a colonoscopy after receiving an abnormal result on a blood-based test for colon cancer. Despite its non-invasive nature, the test only works if individuals complete the recommended follow-up procedure. Researchers examined Medicare claims data for over 6,000 people who took the Shield test between 2022 and 2024 and found that only 49% completed the necessary follow-up colonoscopy within six months. The findings highlight the need for strategies to ensure timely follow-up with patients who receive abnormal test results.

Key Takeaways:

  • A study of over 6,000 patients who took the Shield blood-based test for colon cancer found that only 49% completed a follow-up colonoscopy within six months after receiving an abnormal result.
  • The rate of follow-up colonoscopy increased to 56% when the researchers extended the follow-up period to two years.
  • The study found that patients using Medicare Advantage programs were significantly less likely to undergo follow-up colonoscopy compared to those with private insurance.
  • The study's findings suggest that blood-based colorectal cancer screening technologies must be accompanied by strategies to ensure timely follow-up to effectively diagnose and treat the disease.

Statistics:

  • 52,900: the number of expected deaths from colorectal cancer in 2025, according to the American Cancer Society.
  • 49%: the percentage of patients who completed follow-up colonoscopy within six months after receiving an abnormal result on the Shield test.
  • 56%: the percentage of patients who completed follow-up colonoscopy within two years after receiving an abnormal result on the Shield test.
  • 452: the number of patients who received an abnormal result on the Shield test.
  • 6,000+: the number of patients who took the Shield test between 2022 and 2024.

Sources:

  • University of California Los Angeles, news release, July 29, 2025
  • Gastroenterology, July 29, 2025