From the Guidelines
The recommended interval for screening after a polyp removal procedure is determined based on the findings from the initial colonoscopy, particularly the number, size, and histology of polyps removed, with guidelines suggesting 5-10 years for low-risk patients, 3 years for those with 3-10 adenomas or high-risk features, and less than 3 years for those with more than 10 adenomas 1.
Key Considerations
- The number, size, and histology of polyps removed are crucial in determining the screening interval.
- Patients with 1-2 small (<10mm) tubular adenomas with low-grade dysplasia are considered low-risk and may have a 5-10 year follow-up interval.
- Those with 3-10 adenomas, any adenoma ≥10mm, or any adenoma with villous features or high-grade dysplasia are considered higher risk and should have a 3-year follow-up colonoscopy.
- Patients with more than 10 adenomas should have a follow-up in less than 3 years.
- Additional risk factors such as family history of colorectal cancer, quality of bowel preparation, and completeness of polyp removal may influence the screening interval.
Surveillance Recommendations
- For patients with small rectal hyperplastic polyps, a 10-year follow-up interval is recommended, unless they have a hyperplastic polyposis syndrome, which requires more intensive follow-up 1.
- For patients with sessile adenomas that are removed piecemeal, follow-up colonoscopy at 2-6 months is recommended to verify complete removal, and subsequent surveillance should be individualized based on the endoscopist's judgment 1.
- The British Society of Gastroenterology and Association of Coloproctology of Great Britain and Ireland recommend that people with high-risk findings on a surveillance colonoscopy should undergo a further surveillance colonoscopy at an interval of 3 years, while those with no high-risk findings should cease colonoscopic surveillance and participate in the national bowel screening programme when invited 1.
From the Research
Recommended Screening Intervals
The recommended interval for screening after a polyp removal procedure varies depending on the type and number of polyps removed, as well as the patient's risk factors.
- For patients with 1-4 adenomas <10 mm with low-grade dysplasia, the European Society of Gastrointestinal Endoscopy (ESGE) and British Society of Gastroenterology (BSG) guidelines do not recommend colonoscopic surveillance, instead recommending participation in routine CRC screening programs 2.
- The US Multi-Society Task Force (USMSTF) recommends surveillance colonoscopies 7-10 years after diagnosis of 1-2 tubular adenomas <10 mm and 3-5 years for 3-4 tubular adenomas of the same size 2.
- For patients with advanced adenomas, a shorter surveillance interval of 3 years is recommended by the USMSTF 2.
- A study published in 1993 found that colonoscopy performed three years after colonoscopic removal of adenomatous polyps detects important colonic lesions as effectively as follow-up colonoscopy after both one and three years, recommending an interval of at least three years before follow-up colonoscopy 3.
- Another study published in 2022 found that longer post-polypectomy surveillance intervals are associated with increased colorectal neoplasia detection at surveillance, and recommends a 3-year surveillance interval for high-risk patients to ensure timely CRC detection 4.
Factors Influencing Surveillance Intervals
Several factors can influence the recommended surveillance interval, including:
- Type and number of polyps removed: patients with advanced adenomas or multiple polyps may require shorter surveillance intervals 2, 4.
- Patient risk factors: patients with a family history of colorectal cancer or other risk factors may require shorter surveillance intervals 4.
- Quality of bowel prep: adequate bowel prep is essential for effective surveillance colonoscopy 5.
- Endoscopist experience: while experience may not affect adherence to guidelines, it is essential for accurate diagnosis and removal of polyps 5.
Adherence to Guidelines
Studies have shown that adherence to post-polypectomy surveillance guidelines is generally high among academic gastroenterologists, with one study finding an adherence rate of over 85% 5.