Long-term risk of colorectal cancer after adenoma removal: a population-based cohort study
- Vanessa Cottet1,2,3,
- Valérie Jooste1,2,
- Isabelle Fournel1,2,
- Anne-Marie Bouvier1,2,3,4,5,
- Jean Faivre1,2,3,
- Claire Bonithon-Kopp1,2,4,5
- 1INSERM, UMR 866, Dijon, France
- 2Université de Bourgogne, Registre Bourguignon des Cancers Digestifs, Dijon, France
- 3CHRU Dijon, Dijon, France
- 4INSERM, CIE1, Dijon, France
- 5CHRU Dijon, Centre d'Investigation clinique-Epidémiologie clinique, Dijon, France
- Correspondence to Dr Vanessa Cottet, INSERM, UMR 866, Faculté de Médecine, BP 87900, F-21079 Dijon Cedex, France;
Contributors VC was responsible for study design, acquisition of data, statistical analysis, interpretation of data and manuscript writing. VJ was involved in the statistical analysis, interpretation of data and drafting of the manuscript. IF was involved in data analysis and manuscript editing. A-MB provided significant advice and was involved in acquisition of data and critical revision of the manuscript. JF was involved in study concept, interpretation of data and manuscript writing. CB-K obtained funding and was responsible for study coordination, study design, analysis plan, interpretation of data and manuscript writing. VC had full access to all the data in the study and had final responsibility for the decision to submit for publication.
- Revised 15 September 2011
- Accepted 16 September 2011
- Published Online First 22 November 2011
Background Previous studies examining the incidence of colorectal cancer after polypectomy have provided discordant findings. The aim of this study was to compare the risk of colorectal cancer after adenoma removal in routine clinical practice with the risk in the general population.
Design Cohort study based on detailed data from a population-based registry that has collected all cases of both colorectal cancers and adenomas diagnosed in a clearly-defined population since 1976.
Setting French administrative area of Côte-d'Or (Burgundy).
Methods Residents of the area diagnosed for the first time with colorectal adenoma between 1990 and 1999 were included (n=5779). Initial and follow-up data until December 2003 were used to calculate the colorectal cancer standardised incidence ratio (SIR) and cumulative probabilities after adenoma removal.
Results After a median follow-up of 7.7 years, 87 invasive colorectal cancers were diagnosed whereas 69 cases were expected. Compared with the general population, the overall SIR was 1.26 (95% CI 1.01 to 1.56). The risk of colorectal cancer depended on the characteristics of the initial adenoma (SIR 2.23 (95% CI 1.67 to 2.92) for advanced adenomas and 0.68 (95% CI 0.44 to 0.99) for non-advanced adenomas). In cases of advanced adenomas, the SIR was 1.10 (95% CI 0.62 to 1.82) in patients with colonoscopic follow-up and 4.26 (95% CI 2.89 to 6.04) in those without. The 10-year cumulative probabilities of colorectal cancer were, respectively, 2.05% (95% CI 1.14% to 3.64%) and 6.22% (95% CI 4.26% to 9.02%).
Conclusions In routine practice, the risk of colorectal cancer after adenoma removal remains high and depends both on initial adenoma features and on colonoscopy surveillance practices. Gastroenterologists should encourage patients to comply with long-term colonoscopic surveillance.
- Colorectal cancer risk
- colorectal adenomas
- colonoscopic surveillance
- population-based registry
- cancer epidemiology
- dietary - colon cancer
- cancer registries
- cancer prevention
- colorectal cancer
- dietary factors
Funding This work was supported in part by the French Ministry of Health (PHRC), the National Institute of Medical Research (INSERM), the Regional Council of Burgundy and the ‘Fondation de France’.
Competing interests None.
Ethics approval Ethics approval was provided by Burgundy Medical Ethics Committee and the National Commission for Data Processing and Liberties (CNIL).
Provenance and peer review Not commissioned; externally peer reviewed.