After Bariatric Surgery, Colon Cancer Risk Drops to Same As General Population Interview with:
Dr Laurent Bailly MD, PhD
Département de Santé Publique,
CHU Nice, Hôpital Archet 1. Niveau1
NICE France What is the background for this study?

Response: Obesity is known to increase cancer incidence and notably colorectal cancer incidence. Bariatric surgery is an effective treatment of obesity however the association of this surgery with the colorectal cancer remained controversial.

We used the French National Health Insurance Information System to conduct a nationwide retrospective cohort study, between 2009 and 2018, of patients hospitalized in France with a diagnosis of obesity.

We followed more than 1 million obese individuals aged 50 to 75 years and free of colorectal cancer at baseline, some of them did undergo bariatric surgery and others did not. What are the main findings?

Response: In obese individuals who did not undergo bariatric surgery 12,629 (1.3%) new colorectal cancer cases (1.2%) were diagnosed, whereas only 9,417 cases were expected.

On the contrary, in obese individuals who did undergo bariatric surgery 423 new colorectal cancer cases (0.6%) were observed, whereas 428 cases were expected. What should readers take away from your report?

Response: Following bariatric surgery individuals with obesity share the same risk of colorectal cancer as the general population whereas for patients who did not undergo bariatric surgery the risk of developing a colorectal cancer is 34% above that of the general population, and even 80% above for the patients aged 50 to 59. What recommendations do you have for future research as a result of this work?

Response: Our study was an observational study, it would be interesting to follow-up individuals with obesity after bariatric surgery to determine the respective part of weight loss, physical activity and hormonal change in decreasing the risk of colorectal cancer.

No disclosures


Bailly L, Fabre R, Pradier C, Iannelli A. Colorectal Cancer Risk Following Bariatric Surgery in a Nationwide Study of French Individuals With Obesity. JAMA Surg. Published online March 11, 2020. doi:10.1001/jamasurg.2020.0089





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Last Updated on March 13, 2020 by Marie Benz MD FAAD