Colonoscopy Surveillance Calculator
Fill in the findings of the two most recent colonoscopies to determine the appropriate surveillance interval. Please note if there are other indications for colonoscopy such as family history or a polyposis syndrome, recommended surveillance intervals may differ from those shown below (see tools for family risk calculation and syndromes).
Index Colonoscopy
Conventional adenomas
Were any of these >= 10mm?

Adenomas over 20mm are more likely to be excised piecemeal and should be considered under the large and laterally spreading adenomas section

Did any adenoma have high grade dysplasia or villiosity?
Clinically significant serrated lesions

Surveillance is recommended for "clinically significant" serrated polyps:
- sessile serrated adenomas
- traditional serrated adenomas
- hyperplastic polyps >= 10mm.

Were any of these advanced (>=10 mm, dysplasia or TSA)
Surveillance interval
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Second Colonoscopy
Conventional adenomas
Were any of these >= 10mm?
Did any adenoma have high grade dysplasia or villiosity?
Clinically significant sessile serrated lesions
Were any of these advanced (>=10 mm, dysplasia or TSA)
Surveillance interval
Click image to enlarge
This tool is based on the guidelines released by the Cancer Council Australia Clinical Guidelines Network. All tables displayed are from the short form guideline published by the same group.1 All calculations should be checked prior to clinical use.

A note on surveillance intervals
In some instances, the current short form guidelines are unclear as to the appropriate follow-up period, and different sections may give conflicting results. For example, if five sessile serrated polyps are found on index colonoscopy, the surveillance should be done in one year (according to table 9a). If an adenoma is also found (a total of six polyps), table 9b would normally be used - this would suggest a surveillance colonoscopy in three years.
In cases such as the one listed above, this tool will suggest the shorter of the two surveillance periods.




See the full guidelines on the Australian Clinical Guidelines Wiki.
Last updated 16/6/2020 by Adam Haig
References:
  1. Cancer Council Australia Surveillance Colonoscopy Guidelines Working Party. Clinical practice guidelines for surveillance colonoscopy. Sydney: Cancer Council Australia. [Version URL: https://wiki.cancer.org.au/australiawiki/index.php?oldid=208067, cited 2020 May 16]. Available from: https://wiki.cancer.org.au/australia/Guidelines:Colorectal_cancer/Colonoscopy_surveillance.