Post-Polypectomy Surveillance Recommendations Frequently Asked Questions for Healthcare Providers

Find answers to frequently asked questions about ColonCancerCheck’s post-polypectomy surveillance recommendations.

How were the recommendations developed?

A panel of experts in gastroenterology, pathology and colorectal surgery guided the development of the recommendations.

ColonCancerCheck first conducted an evidence review of English language post-polypectomy surveillance guidelines published from 2007 to 2014 using PubMed. Following the evidence review, the expert panel chose to use the same polyp classification framework as the 2012 U.S. Multi-Society Task Force on Colorectal Cancer^[1] and the 2013 Canadian Association of Gastroenterology guidelines,^[2] which classifies adenomas into high risk and low risk groups. While some European guidelines^[3] include an intermediate risk category, the expert panel aligned with the high and low risk classifications most familiar to Ontario endoscopists.

The evidence review found a lack of consensus in guidelines from other jurisdictions on the management of low risk adenomas. To address this, ColonCancerCheck conducted a systematic review and meta-analysis examining literature published between January 2006 and July 2015 to evaluate the risk of developing high risk adenomas, developing colorectal cancer or dying from colorectal cancer in people with low risk adenomas found during their initial colonoscopy.^[4]

Based on the findings, ColonCancerCheck drafted surveillance recommendations and sent them to national and international stakeholders for review. Stakeholder feedback was incorporated into the final program recommendations.

How do the new recommendations differ from the previous ColonCancerCheck recommendations?

When ColonCancerCheck was established in 2008, the program adopted the 2006 post-polypectomy surveillance guidelines from the U.S. Multi-Society Task Force on Colorectal Cancer.^[5] This guideline recommended the next test and surveillance interval (i.e., the time until the next test) depending on the findings of the baseline or initial colonoscopy.^[5]

Since then, new evidence has emerged, prompting a review and update of ColonCancerCheck’s post-polypectomy surveillance recommendations. The updated recommendations are based, where possible, on findings from the initial and subsequent colonoscopies. Surveillance intervals can be adjusted based on the findings of the most recent colonoscopy.

The new post-polypectomy surveillance recommendations state that average risk people (i.e., ages 50 to 74 with no symptoms and no first-degree relatives with colorectal cancer) with no polyps or hyperplastic polyps found during their initial colonoscopy can return to screening with the fecal immunochemical test (FIT) in 10 years.

Additionally, the new recommendations no longer recommend surveillance colonoscopy for people at average risk for colorectal cancer who had 1 or 2 low risk adenomas found during their initial colonoscopy. ColonCancerCheck now considers people with 1 or 2 low risk adenomas to be at average or lower-than-average risk, and recommends they return to average risk screening with FIT 5 years after their initial colonoscopy. This recommendation is based on a systematic review and meta-analysis examining literature published between January 2006 and July 2015 that evaluated the risk of developing high risk adenomas, developing colorectal cancer or dying from colorectal cancer in people who were found to have low risk adenomas during their initial colonoscopy.^[4]

Why does ColonCancerCheck no longer recommend surveillance colonoscopy for people with low risk adenomas?

ColonCancerCheck’s surveillance recommendations are evidence based. They are designed to ensure the benefits of surveillance colonoscopies outweigh their potential harms. ColonCancerCheck now considers that people with 1 or 2 low risk adenomas are at average or lower-than-average risk. Therefore, surveillance colonoscopy is no longer recommended for these people. Instead, they should return to average risk screening with the fecal immunochemical test (FIT) 5 years after their initial colonoscopy.

These recommendations were developed after ColonCancerCheck conducted a systematic review and meta-analysis examining literature published between January 2006 and July 2015 on the risk of developing high risk adenomas, developing colorectal cancer or dying from colorectal cancer after the removal of low risk adenomas.^[4] The review found that people who had low risk adenomas during their initial colonoscopy were at lower risk of developing colorectal cancer and dying from colorectal cancer when compared with the general population.

However, the review also found that, when compared with people with a normal prior colonoscopy, people with prior low risk adenomas have a small but statistically significant increased risk of developing high risk adenomas.^[4] Based on the literature available at the time, it was not possible to determine if this statistically significant increased risk of developing high risk adenomas translates to an increased risk of developing colorectal cancer or dying from the disease when compared with people with a prior normal colonoscopy.

Due to this lack of clarity, ColonCancerCheck took a conservative approach and advised that people with low risk adenomas found during their initial colonoscopy return to average risk screening with FIT earlier than people with normal colonoscopy findings (i.e., in 5 years instead of 10 years).

Since then, numerous cohort studies with long-term follow-up found that the risk of developing colorectal cancer and the risk of dying from colorectal cancer is similar between people with prior low risk adenomas and no adenomas at colonoscopy.^[6]^[7]^[8]^[9]

In addition, several recent studies have also strengthened the evidence that people with low risk adenomas have a lower risk of developing colorectal cancer and dying from colorectal cancer when compared with the general population.^[10]^[11]

This emerging body of evidence supports ColonCancerCheck’s recommendation to not perform colonoscopy surveillance in people with prior low risk adenomas, but to instead screen these individuals with FIT.^[8]^[10]^[11]

How do ColonCancerCheck’s recommendations compare with other guidelines?

Canadian Association of Gastroenterology guideline

ColonCancerCheck’s recommendations use the same high and low risk polyp classification system as the 2013 Canadian Association of Gastroenterology guideline, and the majority of the program’s post-polypectomy surveillance recommendations align with this guideline.^[2] However, the two differ in their recommendations for people with 1 or 2 low risk adenomas. The Canadian Association of Gastroenterology guideline recommends surveillance colonoscopy, while ColonCancerCheck recommends returning to average risk screening with the fecal immunochemical test (FIT) 5 years after the initial colonoscopy.

ColonCancerCheck’s recommendations are based on a systematic review and meta-analysis on the risk of developing high risk adenomas, developing colorectal cancer or dying from colorectal cancer in people who are found to have low risk adenomas during their initial colonoscopy.^[4] This analysis revealed that people with low risk adenomas have a significantly lower risk of developing colorectal cancer and dying from colorectal cancer than the general population.^[4]

In addition, more recent evidence suggests that people with low risk adenomas have the same risk of developing colorectal cancer and dying from colorectal cancer as those who had no adenomas found during their initial colonoscopy.^[6]^[7]^[8]^[9] ColonCancerCheck’s recommendations are designed to ensure that the benefits of surveillance colonoscopies outweigh their potential harms. Therefore, ColonCancerCheck no longer recommends surveillance colonoscopy for people with 1 or 2 low risk adenomas.

U.S. Multi-Society Task Force on Colorectal Cancer guideline

ColonCancerCheck’s recommendations are comparable to the 2020 post-polypectomy guideline from the U.S. Multi-Society Task Force on Colorectal Cancer. This guideline concluded that, when compared to the general population, most people with 1 or 2 small adenomas (less than 10 millimeters) found during their initial colonoscopy are at lower than average risk for colorectal cancer after polypectomy.^[12] It also concluded that it is uncertain whether surveillance colonoscopy performed in these people has any impact on future risk of developing colorectal cancer or dying from the disease. The Task Force recommends that people with low risk findings be managed similarly to the average risk population, which in the United States context means performing colonoscopy in 7 to 10 years.^[12]

European and British guidelines

ColonCancerCheck’s recommendations also align with the 2013 European Society of Gastrointestinal Endoscopy’s surveillance guideline and the 2020 British Society of Gastroenterology’s surveillance guideline. Both guidelines recommend that people return to average risk screening with FIT if they are found to have low risk adenomas during their initial colonoscopy.^[3]^[13]

Do people with a family history of colorectal polyps require screening colonoscopy?

Up to half of the population over age 50 may have colorectal polyps,^[3] so it is not uncommon for people to have a family history of polyps. People with a family history of polyps are considered average risk and should not have surveillance colonoscopy. Instead, they should be screened with the fecal immunochemical test according to ColonCancerCheck’s average risk screening recommendations.

However, people with a family history of colorectal cancer in 1 or more first-degree relatives (parent, brother, sister, child) are at increased risk for colorectal cancer. They should be screened with colonoscopy starting at age 50, or 10 years earlier than the age their relative was diagnosed, whichever occurs first, as per ColonCancerCheck’s increased risk screening recommendations.

See the Colorectal Cancer Screening Summary for ColonCancerCheck’s average and increased risk screening recommendations.

What are the surveillance recommendations for people at increased risk for colorectal cancer due to a family history of the disease?

Review the findings of the initial colonoscopy when deciding surveillance recommendations for people at increased risk due to 1 or more first-degree relatives (parent, child, brother or sister) diagnosed with the disease.

While ColonCancerCheck recommends people at average risk screen with FIT after a normal colonoscopy or when 1 or 2 low risk adenomas are found, people at increased risk should continue to have follow-up screening with colonoscopy, as per ColonCancerCheck’s increased risk recommendations (see Colorectal Cancer Screening Recommendations Summary).

The recall interval for people with a family history of colorectal cancer and normal colonoscopy should also be based on ColonCancerCheck’s increased risk recommendations. For all other findings at the initial colonoscopy, follow the interval in the surveillance recommendations.

Do the recommendations apply to people under age 50?

ColonCancerCheck’s recommendations for post-polypectomy surveillance are based on the available scientific literature, which tends to focus on screen-eligible populations (i.e., people age 50 and older). There is limited scientific literature on post-polypectomy surveillance and cancer risk in people under age 50.

When making surveillance recommendations for people under 50, endoscopists should consider:

family history of colorectal cancer
findings at colonoscopy
whether someone is close to age 50

Further considerations depending on risk of developing colorectal cancer for people under age 50

People with a family history of colorectal cancer in a first-degree relative

Review the findings of the initial colonoscopy when deciding surveillance recommendations for people at increased risk due to 1 or more first-degree relatives (parent, child, brother or sister) diagnosed with the disease.

While ColonCancerCheck recommends people at average risk screen with FIT after a normal colonoscopy or when 1 or 2 low risk adenomas are found, people at increased risk should continue to have follow-up screening with colonoscopy, as per ColonCancerCheck’s increased risk recommendations (see Colorectal Cancer Screening Recommendations Summary).

The recall interval for people with a family history of colorectal cancer and normal colonoscopy should also be based on ColonCancerCheck’s increased risk recommendations. For all other findings at the initial colonoscopy, follow the interval in the surveillance recommendations.

People with no family history of colorectal cancer in a first-degree relative

ColonCancerCheck does not recommend colonoscopy for average risk screening or people under age 50 who have no first-degree relatives with colorectal cancer.

If someone under age 50 with no first-degree relatives with colorectal cancer has had a colonoscopy that reveals screen-relevant findings (i.e., adenomas or serrated polyps), the post-polypectomy recommendations are at the endoscopist’s discretion. The recommendation should consider the patient’s age, preferences, health status and the presence of other risk factors.