Roel Bogie

Optimizing post-polypectomy surveillance: A practical guide for the endoscopist

with large numbers of adenomas or serrated polyps, referral for genetic screening to underlying polyposis syndromes is advised. 3 A shorter surveillance interval is also recommended for these patients by some guidelines, because of a larger appearing chance of missing neoplasia. 9 Although a general consensus on the significance of sessile serrated lesions appears from the surveillance guidelines, the surveillance intervals itself differ. Studies suggesting more metachronous CRCs in patients with sessile serrated adenomas and traditional serrated adenomas are retrospective and based on very few cases. 10, 11 A larger prospective study still had in absolute counts a low number of CRC cases among patients with sessile serrated lesions. 12 However, a large retrospective case-control study showed a strong association between sessile serrated lesions and metachronous CRC occurrence. 13 Additionally, molecular profiling shows that the so-called serrated pathway is found in about a third of all CRCs. The same molecular features, a CpG island methylation phenotype and BRAF gene mutations, occur frequently in sessile serrated lesions. 14 In conclusion, additional data have provided evidence that the risk of metachronous CRC after a high-quality clearing colonoscopy is lower than previously thought. This additional information has resulted in less intense surveillance regimens by the described guidelines. Data that have become available on sessile serrated lesions have resulted in a more generally accepted consensus about sessile serrated lesions being significant for metachronous CRCs. This led more often to shorter surveillance intervals for patients with these lesions. Evaluation of current surveillance regimens in the upcoming years will reveal whether the current strategies are helpful or not, just as recently published studies have changed the follow-up regimens for patients with conventional adenomas.

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Table 7.3: Overview of four of the most relevant post-polypectomy surveillance guidelines, comparing the old and the new advice.

Guideline ESGE guidelines 3

Old groups Low risk ≤2 tubular adenomas, all <10mm High risk ≥3 adenomas / HGD / size ≥10mm

New groups

Old advice Back to screening/ colonoscopy after 10 yrs

New advice Back to screening/ colonoscopy after 10 yrs

Low risk ≤4 adenomas, all <10mm High risk ≥5 adenomas / HGD / size ≥10mm / SP ≥10mm or dysplastic Low risk <5 adenomas/ SPs with no advanced features / ≤1 advanced adenoma/SP

Surveillance after 3 yrs

Surveillance after 3 yrs

BSG/ACGBI/PHE guidelines 4

Low risk 1-2 adenomas <10mm

Surveillance after 5 yrs

Back to screening

Intermediate risk 3-4 adenomas <10mm / ≥1 adenomas ≥10mm in size

-

Surveillance after 3 yrs

-

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