Colonoscopy surveillance interval
Enter the polyps removed and see the surveillance interval the guideline sets, with the rule and its source.
Canada has no maintained national post-polypectomy guideline; the provinces differ.
No lesion at this exam — scored as a normal colonoscopy.
A normal colonoscopy — no surveillance required; the patient resumes routine screening.
Show exact guideline wording
Individuals with no polyps or only hyperplastic polyps < 10 mm* | No surveillance required. Resume screening as per: BCGuidelines.ca: Screening for the Purposes of Colorectal Cancer Prevention and Detection in Asymptomatic Adults
Table 1: Surveillance Recommendations, row 1, page 3
How BCGuidelines 2022 sets the colonoscopy surveillance interval
British Columbia's BCGuidelines (2022) sets post-polypectomy intervals from a single grid that pools all precancerous lesions, both adenomas and serrated lesions, by risk and by count rather than tracking adenoma subtypes on their own. One to four low-risk lesions return at 10 years, while 5 or more low-risk lesions or any high-risk lesion return at 3 years, and a normal exam or only small hyperplastic polyps goes back to fecal immunochemical test (FIT) screening. High risk here means an advanced adenoma: villous features, high-grade dysplasia, a lesion 10 mm or larger, or one of the higher-risk serrated types.
| Finding at the baseline colonoscopy | Surveillance interval |
|---|---|
| No polyps, or only hyperplastic polyps under 10 mm | No surveillance; return to FIT screening |
| 1 to 4 low-risk precancerous lesions (tubular adenomas under 10 mm with low-grade dysplasia only, or sessile serrated lesions (SSLs) without dysplasia) | Colonoscopy in 10 years |
| 5 or more low-risk precancerous lesions (tubular adenomas under 10 mm with low-grade dysplasia only, or SSLs without dysplasia) | Colonoscopy in 3 years |
| 1 or more high-risk lesions (advanced adenoma): villous features, high-grade dysplasia, an adenoma or SSL 10 mm or larger, an SSL with cytologic dysplasia, a traditional serrated adenoma (TSA), or a hyperplastic polyp 10 mm or larger | Colonoscopy in 3 years |
| Large precancerous lesion removed piecemeal | Repeat colonoscopy at 6 months to check the resection site; later intervals at the endoscopist's discretion |
| 10 or more precancerous lesions removed over a lifetime | No set colonoscopy interval; referral to the Hereditary Cancer Program |
BC keeps 1 to 4 low-risk lesions on a 10-year colonoscopy, longer than the US, which surveils 3 to 4 such lesions at 3 to 5 years, and unlike Ontario, which returns 1 to 2 low-risk adenomas to FIT screening in 5 years.
Source: BCGuidelines.ca — Colorectal Cancer Part 2: Follow-up of Colorectal Cancer and Precancerous Lesions (Polyps), 2022 ↗. This is the baseline colonoscopy table; enter specific findings in the calculator above for the rule and its exact wording.
After a surveillance colonoscopy
BCGuidelines sets the next interval from the findings at each surveillance exam. Any exam with no precancerous lesion returns the patient to a faecal test in 10 years; the 3-year track de-escalates to 5 years once an exam shows only 0 to 4 low-risk lesions.
The calculator gives a timeframe wherever the guideline or the screening programme sets one, and labels anything the guideline does not itself specify.
Age, stopping, and risk factors
Age. No age cap for polyp surveillance. Significant comorbidity, very advanced age, or limited life expectancy: surveillance is not routinely offered.
Risk factors. Hereditary syndromes, inflammatory bowel disease, and colorectal cancer follow-up are covered separately.
Colonoscopy surveillance intervals: quick answers
How soon should a colonoscopy be repeated after polypectomy under British Columbia (BCGuidelines 2022)?
British Columbia's BCGuidelines (2022) sets the interval from one grid pooling adenomas and serrated lesions by risk and count. One to four low-risk precancerous lesions return to colonoscopy in 10 years. Five or more low-risk lesions, or any high-risk lesion, move to colonoscopy in 3 years.
What is the surveillance interval after removing one or two small tubular adenomas in British Columbia?
For one to four low-risk precancerous lesions, meaning tubular adenomas under 10 mm with low-grade dysplasia (LGD) only, or sessile serrated lesions (SSLs) without dysplasia, BCGuidelines (2022) sets colonoscopy in 10 years. That is longer than the United States, which surveils three to four such lesions at 3 to 5 years.
Does the number of low-risk polyps change the colonoscopy surveillance interval in British Columbia?
Yes. BCGuidelines (2022) keeps one to four low-risk precancerous lesions on a 10-year colonoscopy, but five or more low-risk lesions shorten the interval to colonoscopy in 3 years. Count alone raises the risk tier here, even without any advanced or high-risk feature.
What surveillance interval applies to an advanced adenoma with villous histology or high-grade dysplasia in British Columbia?
BCGuidelines (2022) treats a high-risk lesion, an advanced adenoma with villous features, high-grade dysplasia (HGD), or a lesion 10 mm or larger, as warranting colonoscopy in 3 years. The same 3-year interval applies whether one or several high-risk lesions are found.
How does BCGuidelines (2022) handle surveillance for sessile serrated lesions after polypectomy?
BCGuidelines (2022) pools sessile serrated lesions (SSLs) with adenomas in one grid. One to four SSLs without dysplasia count as low-risk and return to colonoscopy in 10 years. An SSL 10 mm or larger, or with cytologic dysplasia, is high-risk and moves to colonoscopy in 3 years.
What follow-up does British Columbia recommend after piecemeal removal of a large polyp?
BCGuidelines (2022) recommends a repeat colonoscopy at 6 months after a large precancerous lesion is removed piecemeal, to check the resection site for residual tissue. Later surveillance intervals are left to the endoscopist's discretion rather than fixed by the risk-and-count grid that governs other polyp findings.
When does a patient return to stool-based (FIT) screening instead of colonoscopy in British Columbia?
A normal colonoscopy, or one finding only hyperplastic polyps under 10 mm, needs no surveillance and returns to fecal immunochemical test (FIT) screening. A cleared colonoscopy returns to FIT in 10 years, then FIT every 2 years for ages 50 to 74.
For the guideline sources and side-by-side interval tables across all the guidelines, see the colonoscopy surveillance guideline reference.
Reference tool for health professionals. Not medical advice, not a medical device, and does not make or replace a clinical decision. The calculation runs in your browser; the findings you enter are not transmitted or stored. The Aescia clinical team reviews this tool periodically against the source guidelines and updates it when they change, but guidelines are revised without notice; verify against the current version before acting. If you notice an error, tell us at contact@aesciahealth.com.
Last reviewed against the source guidelines on 14 July 2026.
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