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.
Not for intervals after a surveillance colonoscopy.
Tick if any apply.
| Prevalence | Histopathology | Guideline interval |
|---|---|---|
| ~45–60% | Tubular adenoma | 5 years |
| ~20–30% | Hyperplastic | 10 years |
| ~5–15% | Tubulovillous / villous | 3 years |
| ~1–8% | Sessile serrated | 5 years |
| <1% | Traditional serrated | 3 years |
How ACRCSP sets the colonoscopy surveillance interval
The Alberta Colorectal Cancer Screening Program (ACRCSP) sets post-polypectomy intervals from the single most advanced finding at a high-quality baseline colonoscopy, confirmed on final pathology. It is distinctive in routing the lowest-risk findings back to stool-based screening: a normal exam, small hyperplastic polyps, and one to two small adenomas all return to the fecal immunochemical test (FIT) rather than to a scheduled colonoscopy. Colonoscopy surveillance at one, three, or five years is reserved for higher adenoma counts, large or advanced lesions, the serrated categories, and piecemeal removals.
| Finding at the baseline colonoscopy | Surveillance interval |
|---|---|
| Normal colonoscopy or no polyps | FIT in 10 years |
| Hyperplastic polyps under 10 mm | FIT in 10 years |
| 1 to 2 tubular adenomas under 10 mm | FIT in 5 years |
| 3 to 4 tubular adenomas under 10 mm | Colonoscopy in 5 years |
| 5 to 10 tubular adenomas under 10 mm, any adenoma 10 mm or larger, or villous/tubulovillous features or high-grade dysplasia | Colonoscopy in 3 years |
| More than 10 tubular adenomas on a single colonoscopy | Colonoscopy in 1 year, and consider genetic counselling |
| 1 to 2 sessile serrated lesions (SSL) under 10 mm | Colonoscopy in 5 years |
| 3 to 10 sessile serrated lesions under 10 mm | Colonoscopy in 3 years |
| Sessile serrated lesion over 10 mm, traditional serrated adenoma of any size, or sessile serrated lesion with dysplasia of any size | Colonoscopy in 3 years |
| Hyperplastic polyp 10 mm or larger, proximal to the sigmoid colon | Colonoscopy in 3 years |
| Hyperplastic polyp 10 mm or larger, in the rectosigmoid | Colonoscopy in 5 years |
| Serrated polyposis syndrome | Colonoscopy in 1 year |
| Synchronous sessile serrated lesion and tubular adenoma | No recommendation made (insufficient evidence) |
| Piecemeal removal of a large (10 mm or larger) non-pedunculated polyp | First repeat endoscopic assessment in 6 months |
Alberta returns one to two small tubular adenomas to a fecal immunochemical test (FIT) in five years, where the US schedules a surveillance colonoscopy at seven to ten years for the same finding.
Source: Alberta Colorectal Cancer Screening Program (Sadowski et al., J Can Assoc Gastroenterol 2024;7(4):319–328) ↗. This is the baseline colonoscopy table; enter specific findings in the calculator above for the rule and its exact wording.
For common questions and the source behind each rule 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.
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