Roel Bogie

Chapter 7

Update of post-polypectomy surveillance guidelines since 2015 Since the publication of our paper “Optimizing post-polypectomy surveillance: A practical guide for the endoscopist”, most of the described post-surveillance guidelines have been updated with new algorithms. For instance, specific new information about serrated polyps was added. Furthermore, the indications for surveillance colonoscopy have become less extensive. A large retrospective cohort study, investigating findings during follow-up of patients with adenomas, showed that patients with proximal, large (≥10mm) and high-grade dysplastic adenomas seemed to have more benefit from surveillance than the patients with adenomas without these characteristics. The number of patients with cancer during surveillance were low. 1 A second study with similar methodology, that used the old definition of high risk findings including more than two adenomas and villosity, showed similar results. 2 Therefore, an overview of the updated, currently used post polypectomy surveillance guidelines with a comparison of their progenitor guidelines is provided in Table 7.3 . In the European Society of Gastrointestinal Endoscopy (ESGE) polyp surveillance guidelines update, the most liberal surveillance algorithm was chosen. 3 In comparison to the previous version from 2013, less patients need surveillance. Only patients with at least 5 adenomas, with at least one large (≥10mm) adenoma or sessile serrated lesion, or with high grade dysplasia are in need for surveillance after 3 years. 3 The guidelines of the British Society of Gastroenterology and the Association of Coloproctology of Great Britain and Ireland (BSG/ACGBI/PHE) previously identified three risk groups, but simplified to two groups in its updated formats, in a similar way as in the ESGE guidelines. A large subset of cases previously classified as intermediate risk are now classified as low risk. This means that patients previously receiving surveillance after three years will now return to the default colorectal cancer screening program. Surveillance after one year is now replaced by surveillance after three years. 4 The currently applicable US Multi-Society Task Force on Colorectal Cancer (US-MSTF CRC) Guidelines are more complex. While the two previously mentioned updates of the guidelines simplified their surveillance advice, these US guidelines have increased in complexity. The intervals differ between 1 and 10 years. In contrast to the other guidelines, adenomas with villous characteristics and a higher number adenomas remain a significant risk factor in these guidelines. 5 Previous studies showed an association between adenoma villosity and recurrent advanced adenoma. 6 However, a meta-analysis pooling 13 studies showed no significant effect on adenoma recurrence (RR 1.21, 95% CI: 0.97 – 1.45). 7 Furthermore, a recent population-based study with colorectal cancer incidence ratios as outcome instead of adenoma recurrence, showed no effect of villous histology. 8 The ESGE guidelines and BSG/ACGBI/PHE guidelines clearly state that surveillance intervals should reduce the risk of metachronous CRC and not metachronous adenomas while allocating higher impact on papers with this outcome. The US-MSTF guidelines in contrast appear to focus more on uncertainties and are more conservative in their recommendations. 3-5 Recently, also the Japan Gastroenterological Endoscopy Society (JGES) published their updated post-polypectomy surveillance guidelines. In this guideline 3 different surveillance intervals can be distinguished. Noticeable, higher significance is given to the occurrence of high grade dysplasia, or carcinoma in situ as it is called in Japan. 9 All these updated surveillance guidelines agree that high quality index colonoscopy is a prerequisite for the protective effect of colorectal cancer development. 3-5, 9 Concerning patients

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