Follow-Up Colonoscopy Rates After Abnormal Blood-Based CRC Screening Mirror Stool-Based Tests
A retrospective national analysis of closed claims data shows that colonoscopic follow-up (FU-CY) after abnormal blood-based colorectal cancer (CRC) screening results occurs in about half of eligible patients within 6 months—comparable to follow-up rates seen with stool-based screening methods.
“Blood-based tests for CRC are emerging as convenient, noninvasive screening options with potential to address some barriers, increase screening participation, and possibly improve CRC outcomes,” the authors noted. This study examined early real-world follow-up behavior in patients who underwent testing with Shield, a blood-based CRC test approved by the US Food and Drug Administration in July 2024.
Using data from a HIPAA-compliant claims database covering 320 million lives, the analysis included 6068 average-risk adults aged ≥45 years screened with Shield between May 2022 and September 2024. Of 452 individuals with an abnormal result, 228 had ≥6 months of follow-up, and 49% underwent colonoscopy within that time frame. Overall, 56% completed a follow-up colonoscopy at any time.
The mean time to colonoscopy was 66.4 days within 6 months and 98.3 days overall. In adjusted models, patients with Medicare Advantage were significantly less likely to undergo timely FU-CY than those with private insurance (adjusted OR 0.26; 95% CI, 0.11–0.67). Having fewer comorbidities was associated with increased likelihood of timely follow-up (adjusted OR 0.90; 95% CI, 0.82–0.97). Race/ethnicity and geographic region were not significant predictors.
“FU-CY rates after abnormal blood-based CRC screening are comparable to those reported for stool-based tests,” the authors stated.
“As blood-based CRC screening technologies become Food and Drug Administration approved and adopted by physicians and patients, we must prioritize strategies to ensure timely follow-up, similar to those implemented for stool-based screening tests.”
This early data not only supports the potential of blood-based CRC screening to overcome traditional barriers but also underscores a need for improved systems to support follow-up colonoscopy. As the screening landscape evolves, real-world adherence will remain a key marker of effectiveness across modalities.
Reference
Zaki TA, Zhang NJ, Forbes SP, Raymond VM, Das AK, May FP. Colonoscopic follow-up after abnormal blood-based colorectal cancer screening results. Gastroenterology. 2025 Nov;169(6):1301-1303. doi: 10.1053/j.gastro.2025.07.019. Epub 2025 Jul 29. PMID: 40744392.
