A Comparison of Risk Classification Systems of Colorectal Adenomas: A Case-Cohort Study

Henriette C Jodal; Paulina Wieszczy-Szczepanik; Dagmar Klotz; Magnhild Herfindal; Ishita Barua; Petter Tag; Lise M Helsingen; Erle Refsum; Øyvind Holme; Hans-Olov Adami; Michael Bretthauer; Mette Kalager; Magnus Løberg

doi:10.1053/j.gastro.2023.04.028

A Comparison of Risk Classification Systems of Colorectal Adenomas: A Case-Cohort Study

Gastroenterology. 2023 Aug;165(2):483-491.e7. doi: 10.1053/j.gastro.2023.04.028. Epub 2023 May 3.

Authors

Affiliations

¹ Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway; Section of Oncology, Drammen Hospital, Vestre Viken Hospital Trust, Drammen, Norway. Electronic address: h.c.jodal@medisin.uio.no.
² Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Department of Gastroenterology, Hepatology and Clinical Oncology, Centre of Postgraduate Medical Education, Warsaw, Poland.
³ Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway; Department of Pathology, Oslo University Hospital, Oslo, Norway.
⁴ Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway.
⁵ Department of Medicine, Nordland Hospital Bodø, Bodø, Norway.
⁶ Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway; Department of Medicine, Sørlandet Hospital Kristiansand, Kristiansand, Norway.
⁷ Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway; Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden.
⁸ Clinical Effectiveness Research Group, Institute of Health and Society, University of Oslo, Oslo, Norway; Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway; Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, Massachusetts.

PMID: 37146913
DOI: 10.1053/j.gastro.2023.04.028

Abstract

Background & aims: Because post-polypectomy surveillance uses a growing proportion of colonoscopy capacity, more targeted surveillance is warranted. We therefore compared surveillance burden and cancer detection using 3 different adenoma classification systems.

Methods: In a case-cohort study among individuals who had adenomas removed between 1993 and 2007, we included 675 individuals with colorectal cancer (cases) diagnosed a median of 5.6 years after adenoma removal and 906 randomly selected individuals (subcohort). We compared colorectal cancer incidence among high- and low-risk individuals defined according to the traditional (high-risk: diameter ≥10 mm, high-grade dysplasia, villous growth pattern, or 3 or more adenomas), European Society of Gastrointestinal Endoscopy (ESGE) 2020 (high-risk: diameter ≥10 mm, high-grade dysplasia, or 5 or more adenomas), and novel (high-risk: diameter ≥20 mm or high-grade dysplasia) classification systems. For the different classification systems, we calculated the number of individuals recommended frequent surveillance colonoscopy and estimated number of delayed cancer diagnoses.

Results: Four hundred and thirty individuals with adenomas (52.7%) were high risk based on the traditional classification, 369 (45.2%) were high risk based on the ESGE 2020 classification, and 220 (27.0%) were high risk based on the novel classification. Using the traditional, ESGE 2020, and novel classifications, the colorectal cancer incidences per 100,000 person-years were 479, 552, and 690 among high-risk individuals, and 123, 124, and 179 among low-risk individuals, respectively. Compared with the traditional classification, the number of individuals who needed frequent surveillance was reduced by 13.9% and 44.2%, respectively, and 1 (3.4%) and 7 (24.1%) cancer diagnoses were delayed using the ESGE 2020 and novel classifications.

Conclusions: Using the ESGE 2020 and novel risk classifications will substantially reduce resources needed for colonoscopy surveillance after adenoma removal.

Keywords: Adenoma; Case-Cohort; Colorectal Cancer; Screening; Surveillance.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adenoma* / epidemiology
Cohort Studies
Colonic Polyps*
Colonoscopy
Colorectal Neoplasms* / epidemiology
Humans
Risk
Risk Factors