American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the recommended interval to the next colonoscopy for patients with 1-2 tubular adenomas less than 10 mm?

1. 1 year

2. 3-5 years

3. 5-10 years

4. 10 years

The correct answer is: 5-10 years

For patients who have had 1-2 tubular adenomas that are less than 10 mm in size, the current guidelines recommend a follow-up colonoscopy at an interval of 5-10 years. This recommendation is based on findings from studies that indicate a lower risk of colorectal cancer associated with this specific type and size of adenoma. Tubular adenomas are considered low-risk lesions, and the relatively longer interval reflects that they are less likely to progress to cancer compared to larger or more numerous adenomas. In the context of surveillance protocols, a 5-10 year interval addresses both the need for ongoing monitoring and the understanding that patients with low-risk adenomas do not require more aggressive surveillance. This approach aims to balance the benefits of early detection of potential malignancies with the potential harms and costs of more frequent procedures. The other options for shorter intervals, such as annually or every 3-5 years, are more appropriate for patients with findings that confer a higher risk, such as larger adenomas, higher numbers of polyps, or advanced histology. Consequently, the 5-10 year interval for follow-up colonoscopy in this patient group aligns with established guidelines by gastroenterology and oncology societies.