Colorectal cancer and surgery - Regarding the procedures, there were fewer new diagnoses of colorectal cancer after gastric bypass (123 of 22,343 - 0.5%) and sleeve gastrectomy (185 of 35,328 - 0.5%) than after adjustable gastric banding (115 of 16,460 - 0.7%)
Bariatric surgery significantly reduces colorectal cancer (CRC) risk in patients with obesity to the extent that they share the same risk of colorectal cancer as the general population, according to researchers from Université Côte d’Azur, Nice, France. However, for patients with obesity who do not undergo bariatric surgery, the risk is 34% above that of the general population.
The retrospective, population-based, multi-centre, cohort study, ‘Colorectal Cancer Risk Following Bariatric Surgery in a Nationwide Study of French Individuals With Obesity’, published in JAMA Surgery, examined if bariatric surgery is associated with altered risk of colorectal cancer among individuals with obesity.
The study included 1,045,348 individuals with obesity (aged 50 to 75 years) who were free of colorectal cancer at baseline. There were 74 131 patients in the bariatric surgery group (adjustable gastric banding, sleeve gastrectomy, gastric bypass) and 971,217 in the non-surgical cohort. Using data from the French national health insurance information system database, patient in the non-surgical group were followed for a mean 5.3 (2.1) years and a mean 5.7 (2.2) years for those who had surgery.
There were 13,052 incident colorectal cancers (1.2%, (63,649 colorectal benign polyps were diagnosed) and the colorectal cancer was 0.6% in the surgical cohort and 1.3% in the non-surgical group. It was expected that there would be 9,417 cases in the non-surgical group, not the 12,629 observed (standardised incidence ratio of 1.34). In the bariatric surgery cohort, 428 cases were expected and 423 observed (standardised incidence ratio of 1.0). Propensity score–matched hazard ratios in comparable operated vs non-operated groups were 0.68 for colorectal cancer and 0.56 for colorectal benign polyp.
Regarding the procedures, there were fewer new diagnoses of colorectal cancer after gastric bypass (123 of 22,343 - 0.5%) and sleeve gastrectomy (185 of 35,328 - 0.5%) than after adjustable gastric banding (115 of 16,460 - 0.7%). There were also more colorectal benign polyps after adjustable gastric banding (775 of 15,647 - 5.0%) than after gastric bypass (639 of 20,863 - 3.1%) or sleeve gastrectomy (1,005 of 32,680 - 3.1%).