CC BY 4.0 · Endoscopy 2021; 53(04): 402-410
DOI: 10.1055/a-1217-0155
Original article

Heterogeneity in colorectal cancer incidence among people recommended 3-yearly surveillance post-polypectomy: a validation study

Emma C. Robbins
1  Cancer Screening and Prevention Research Group (CSPRG), Department of Surgery and Cancer, Imperial College London, United Kingdom
,
Kate Wooldrage
1  Cancer Screening and Prevention Research Group (CSPRG), Department of Surgery and Cancer, Imperial College London, United Kingdom
,
Iain Stenson
1  Cancer Screening and Prevention Research Group (CSPRG), Department of Surgery and Cancer, Imperial College London, United Kingdom
,
Kevin Pack
1  Cancer Screening and Prevention Research Group (CSPRG), Department of Surgery and Cancer, Imperial College London, United Kingdom
,
Stephen Duffy
2  Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Queen Mary University, London, United Kingdom
,
David Weller
3  Centre for Population Health Sciences, University of Edinburgh, Edinburgh, United Kingdom
,
Theodore Levin
4  Division of Research, Kaiser Permanente Northern California, Oakland, California, United States
,
Carol Conell
4  Division of Research, Kaiser Permanente Northern California, Oakland, California, United States
,
Suzanne Wright
5  Public Health England (PHE) Screening, Sheffield, United Kingdom
,
Claire Nickerson
5  Public Health England (PHE) Screening, Sheffield, United Kingdom
,
Jessica Martin
1  Cancer Screening and Prevention Research Group (CSPRG), Department of Surgery and Cancer, Imperial College London, United Kingdom
,
Amanda J. Cross
1  Cancer Screening and Prevention Research Group (CSPRG), Department of Surgery and Cancer, Imperial College London, United Kingdom
› Author Affiliations

Abstract

Background Colonoscopy surveillance is recommended for patients at increased risk of colorectal cancer (CRC) following adenoma removal. Low-, intermediate-, and high-risk groups are defined by baseline adenoma characteristics. We previously examined intermediate-risk patients from hospital data and identified a higher-risk subgroup who benefited from surveillance and a lower-risk subgroup who may not require surveillance. This study explored whether these findings apply in individuals undergoing CRC screening.

Methods This retrospective study used data from the UK Flexible Sigmoidoscopy Screening Trial (UKFSST), English CRC screening pilot (ECP), and US Kaiser Permanente CRC prevention program (KPCP). Screening participants (50 – 74 years) classified as intermediate-risk at baseline colonoscopy were included. CRC data were available through 2006 (KPCP) or 2014 (UKFSST, ECP). Lower- and higher-risk subgroups were defined using our previously identified baseline risk factors: higher-risk participants had incomplete colonoscopies, poor bowel preparation, adenomas ≥ 20 mm or with high-grade dysplasia, or proximal polyps. We compared CRC incidence in these subgroups and in the presence vs. absence of surveillance using Cox regression.

Results Of 2291 intermediate-risk participants, 45 % were classified as higher risk. Median follow-up was 11.8 years. CRC incidence was higher in the higher-risk than lower-risk subgroup (hazard ratio [HR] 2.08, 95 % confidence interval [CI] 1.07 – 4.06). Surveillance reduced CRC incidence in higher-risk participants (HR 0.35, 95 %CI 0.14 – 0.86) but not statistically significantly so in lower-risk participants (HR 0.41, 95 %CI 0.12 – 1.38).

Conclusion As previously demonstrated for hospital patients, screening participants classified as intermediate risk comprised two risk subgroups. Surveillance clearly benefited the higher-risk subgroup.

Supplementary material



Publication History

Received: 17 October 2019

Accepted: 12 June 2020

Publication Date:
19 August 2020 (online)

© 2020. © 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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