Background

Evidence highlighted the role of metabolic and bariatric surgery (MBS) in reducing the risks associated with cancer-related mortality and cancer incidence. This study aims to explore the impact of MBS on the risk of resectable gastrointestinal cancers.

Methods

We conducted an analysis of the National Inpatient Sample data collected from January 2010 to September 2015. Patients with a BMI >= 35 kg/m² were compared to those with a history of MBS. Event of resectable gastrointestinal tumors were identified with the diagnosis of gastrointestinal tumor and resection. Multivariate logistic regression was used to assess factors associated with resectable gastrointestinal tumors.

Results

A total of 1,868,753 admission with a BMI >= 35 kg/m² were identified, with 5,933 (0.32%) undergoing gastrointestinal tumor resection (623 foregut, 5,310 colorectal). Additionally, 221,701 admission with a history of MBS were identified, among whom 352 (0.16%) underwent gastrointestinal tumor resection (43 foregut, 309 colorectal). The MBS cohort was younger (p<0.001), predominantly female (80.5% vs. 66.1%, p < 0.001), and exhibited a lower Elixhauser Comorbidity Index score (p<0.001). Multivariate analysis revealed a history of MBS as an protective independent factor for the event gastrointestinal tumor resection (OR:0.56, p<0.001); in the colorectal subgroup (OR:0.69, p<0.001) but not in the foregut subgroup (OR:0.74, p=0.074).

Conclusions

Compared to the MBS cohort, patients with obesity have a higher incidence of gastrointestinal tumors despite those being resectable. This effect appears less pronounced in foregut tumors. Further investigation is warranted, considering factors such as obesity duration, timing of cancer occurrence post-MBS and weight-loss/regain.