What is the recommended follow-up interval for a colonoscopy (colo) after removal of a tubular adenoma without dysplasia?

From the Guidelines

For a patient with a tubular adenoma without dysplasia found on colonoscopy, the recommended follow-up colonoscopy should be performed in 5-10 years, depending on additional risk factors. The decision on the exact timing within this interval should be based on other clinical factors, such as prior colonoscopy findings, family history, and the preferences of the patient and judgment of the physician 1. If this was a single, small (less than 10mm) tubular adenoma without high-grade dysplasia, a 7-10 year interval is appropriate. However, if there were 1-2 tubular adenomas with advanced features (≥10mm) or if there were 3-4 small tubular adenomas, a 3-5 year interval would be more appropriate 1.

Some key points to consider in determining the follow-up interval include:

• The size and number of adenomas found
• The presence of villous features or high-grade dysplasia
• The patient's family history of colorectal cancer
• The completeness of adenoma removal

It's also important to note that patients with a history of adenomas are at increased risk for developing future adenomas, and therefore should maintain regular screening thereafter according to age-appropriate guidelines 1. The guidelines for colonoscopy surveillance after polypectomy are based on the understanding that tubular adenomas without dysplasia have a relatively low risk of progressing to colorectal cancer compared to adenomas with high-grade dysplasia or villous features. However, the presence of multiple adenomas, larger size, or a family history of colorectal cancer may warrant shorter surveillance intervals.

From the Research

Follow-up Recommendations for Colo with Tubular Adenoma without Dysplasia

• The study 2 recommends that if CT colonography detects a lesion measuring 6 mm or more, endoscopy and polypectomy should be offered unless contraindicated.
• For lesions smaller than 5 mm, follow-up imaging in 3-5 years is recommended 2.
• The study 3 found that advanced adenomas were generally large (> or = 10 mm in size), and only a small percentage were medium sized (6-9 mm).
• The majority of advanced adenomas had tubular histologic features, followed by tubulovillous, villous, and serrated histologic features 3.
• High-grade dysplasia was uncommon, typically occurring in large lesions 3.
• The study 4 found that CT colonographic screening identified 90% of subjects with adenomas or cancers measuring 10 mm or more in diameter.
• The per-patient sensitivity for detecting adenomas that were 6 mm or more in diameter was 0.78 4.
• The study 5 found that relevant intraluminal anastomotic pathology appears to be very uncommon 1 year after colorectal cancer resection in lower-risk cohorts.
• Unlike colonoscopy, diagnostic contrast-enhanced CT colonography effectively evaluates both the intra- and extraluminal aspects of the anastomosis 5.
• The study 6 found that nonpolypoid adenomas had a very low prevalence (<1%), and advanced pathologic features were uncommon in polyps <10 mm in diameter.
• Most nonpolypoid adenomas are technically visible at CTC, and the prospective sensitivity is similar to that for polypoid adenomas when the interpretation combines both 2D and 3D review 6.

Timing of Repeat Colonoscopy

• Based on the studies, it is recommended to repeat colonoscopy in 3-5 years for lesions smaller than 5 mm 2.
• For lesions measuring 6 mm or more, endoscopy and polypectomy should be offered unless contraindicated 2.
• The exact timing of repeat colonoscopy may depend on the individual patient's risk factors and the results of the initial colonoscopy 3, 4, 5, 6.