Between 2021 and 2024, US endoscopists assigned roughly 3 in 10 patients with one to two nonadvanced adenomas surveillance intervals shorter than the 7-to-10-year guidelines set by the US Multi-Society Task Force. A cross-sectional study of 41,606 average-risk patients published in Clinical Gastroenterology and Hepatology revealed persistent over-surveillance in lower-risk colonoscopy screenings.
- Mechanism of Action: Postpolypectomy surveillance refers to repeat colonoscopy intervals designed to detect metachronous adenomas—new precancerous growths developing after the initial clearing of the bowel.
- Nonadvanced Adenoma Classification: Clinicians classify an adenoma as nonadvanced if it is tubular, measures less than 10 millimeters, and demonstrates neither high-grade dysplasia nor villous histology.
Shifts in US Multi-Society Task Force Intervals and Clinical Adherence
In 2020, the US Multi-Society Task Force updated its postpolypectomy surveillance recommendations. The guidelines lengthened intervals to 7–10 years for patients with one to two nonadvanced adenomas and 3–5 years for those with three to four nonadvanced adenomas. A research team led by Jeffrey M. Hendel, MD, from Kaiser Permanente Medical Center in San Francisco, sought to measure how closely clinical practice aligned with these updated parameters over a multi-year period.
The observational study examined 41,606 average-risk patients who underwent baseline colonoscopies between 2019 and 2024 at a large integrated health system. Among this cohort, 33,787 patients presented with one to two nonadvanced adenomas, while 7,819 presented with three to four. A total of 281 endoscopists performed these baseline procedures, boasting a median of 19 years in clinical practice and a median adenoma detection rate of 52.2% in the prior year.
Adherence varied sharply based on polyp count. Endoscopists adhered to the recommended 7–10-year window for 68.1% of patients with one to two nonadvanced adenomas in 2021, a figure that climbed marginally to 71.9% by 2024. Conversely, adherence for patients with three to four nonadvanced adenomas exceeded 90% across every single year from 2021 to 2024, following the 3–5-year recommendation closely.
| Adenoma Findings | Task Force Interval | Adherence Rate (2021) | Adherence Rate (2024) | Under-Interval Assignment |
|---|---|---|---|---|
| 1-2 Nonadvanced Adenomas | 7-10 Years | 68.1% | 71.9% | 28.1% – 31.9% (< 7 years) |
| 3-4 Nonadvanced Adenomas | 3-5 Years | > 90.0% | > 90.0% | 2.3% – 2.5% (< 3 years) |
Patient Characteristics Linked to Nonadherent Interval Selections
Between 2021 and 2024, between 28.1% and 31.9% of patients with one to two nonadvanced adenomas received instructions to return for a repeat colonoscopy in under 7 years. None in this group were told to wait longer than the 10-year ceiling. For the cohort with three to four nonadvanced adenomas, 2.3% to 2.5% were scheduled for a follow-up in under 3 years, while 6.6% to 7.3% were told to wait longer than 5 years.
Statistical analysis identified specific demographic and clinical factors associated with nonadherent intervals in the low-burden group. Nonadherence toward shorter intervals was more likely among older patients, male participants, individuals with a body mass index (BMI) of 30 or higher, those with a smoking history, and patients managing multiple comorbidities. Endoscopists with 15 to 24 years in practice showed a higher propensity for nonadherent intervals.
Conversely, nonadherent intervals were less likely for patients undergoing diagnostic indications, those of Hispanic ethnicity, Asian race, and with each additional chronological year passing since the 2020 guideline update. For patients presenting with three to four nonadvanced adenomas, no baseline clinical or demographic factors demonstrated a statistically significant link to nonadherence.
Investigators noted distinct behavioral patterns among practicing physicians. Endoscopists routinely bypassed the middle years of the recommended ranges, favoring the outermost bounds instead. For the one-to-two adenoma group, clinicians recommended 10 years in 45.9% to 47.2% of cases, and 7 years in 19.8% to 25.1% of cases. For the three-to-four adenoma group, they prescribed 3 years in 50.9% to 51.5% of cases and 5 years in 37.6% to 39.5% of cases.
The findings suggest that the potential for over-surveillance is substantially more likely for patients with 1-2 versus 3-4 non-advanced adenomas. Guideline developers could consider recommending an interval of, for example, 7 or 10 years in place of the 7-10-year range and 3 or 5 years in place of the 3-5-year range.
Evaluating Single-System Limitations and Future Guideline Trajectories
Several methodological limitations qualify these findings. The study drew its population exclusively from a single integrated health system, potentially limiting the generalizability of these rates to private practices or fee-for-service healthcare models. The observational design leaves open the possibility of residual confounding and unaddressed clinical misclassification. Assessing adherence relied strictly on baseline adenoma findings, which may not capture nuanced clinical context influencing physician decision-making.
The authors suggested that simplifying guideline nomenclature from flexible ranges to explicit single-year targets could reduce unnecessary procedures.
References
- Hendel, JM, et al. Postpolypectomy Surveillance Adherence in an Integrated Health System. Clinical Gastroenterology and Hepatology.
- US Multi-Society Task Force on Colorectal Cancer. Updated Postpolypectomy Surveillance Recommendations.
