Upper gastrointestinal cancer risk following bariatric surgery: meta-analysis
File(s)
Published version
Author(s)
Cooke, Heather
Harewood, Rhea
Hussain, Naveed
Cross, Amanda
Murphy, Gwen
Type
Journal Article
Abstract
Background
Obesity is a growing global epidemic, contributing to heightened risks of multiple chronic diseases, including cancer. Evidence links obesity to several malignancies, including upper gastrointestinal cancers such as oesophageal, gastric, and liver. As the need for effective weight loss intensifies, bariatric surgery is increasingly performed, and procedures have evolved, with Roux-en-Y gastric bypass and sleeve gastrectomy being the most commonly performed surgeries. Given the physiological changes after surgery, the authors conducted a systematic review and meta-analysis to examine the impact of bariatric surgery on upper gastrointestinal cancers.
Methods
Eligible studies investigating bariatric surgery and upper gastrointestinal cancer incidence were identified through MEDLINE, Embase, and citation tracking up to July 2025. Studies reporting on oesophageal, gastric, liver, pancreatic, gallbladder, biliary tract, or small intestinal cancer were included. Random-effects models were used to estimate pooled relative risks (RR) and 95% confidence intervals.
Results
Across 20 included studies, including 1,173,113 patients undergoing bariatric surgery and 4,600,719 patients not undergoing surgery, bariatric surgery, compared with no surgery, was inversely associated with overall upper gastrointestinal cancer risk (RR 0.58, 95% confidence interval (c.i.) 0.48 to 0.71). Specifically, inverse associations were observed for oesophageal (RR 0.63, 95% c.i. 0.40 to 0.98), liver (RR 0.47, 95% c.i. 0.35 to 0.61), and gallbladder cancer (RR 0.33, 95% c.i. 0.17 to 0.65). No significant associations were found for gastric or pancreatic cancers. There were too few studies for biliary tract and small intestinal cancers to allow meta-analyses.
Conclusion
Bariatric surgery appears to reduce the risk of oesophageal, liver, and gallbladder cancers, supporting a role in both weight management and cancer prevention. Standardization in reporting surgical procedures is needed to clarify effects by bariatric surgery type.
Obesity is a growing global epidemic, contributing to heightened risks of multiple chronic diseases, including cancer. Evidence links obesity to several malignancies, including upper gastrointestinal cancers such as oesophageal, gastric, and liver. As the need for effective weight loss intensifies, bariatric surgery is increasingly performed, and procedures have evolved, with Roux-en-Y gastric bypass and sleeve gastrectomy being the most commonly performed surgeries. Given the physiological changes after surgery, the authors conducted a systematic review and meta-analysis to examine the impact of bariatric surgery on upper gastrointestinal cancers.
Methods
Eligible studies investigating bariatric surgery and upper gastrointestinal cancer incidence were identified through MEDLINE, Embase, and citation tracking up to July 2025. Studies reporting on oesophageal, gastric, liver, pancreatic, gallbladder, biliary tract, or small intestinal cancer were included. Random-effects models were used to estimate pooled relative risks (RR) and 95% confidence intervals.
Results
Across 20 included studies, including 1,173,113 patients undergoing bariatric surgery and 4,600,719 patients not undergoing surgery, bariatric surgery, compared with no surgery, was inversely associated with overall upper gastrointestinal cancer risk (RR 0.58, 95% confidence interval (c.i.) 0.48 to 0.71). Specifically, inverse associations were observed for oesophageal (RR 0.63, 95% c.i. 0.40 to 0.98), liver (RR 0.47, 95% c.i. 0.35 to 0.61), and gallbladder cancer (RR 0.33, 95% c.i. 0.17 to 0.65). No significant associations were found for gastric or pancreatic cancers. There were too few studies for biliary tract and small intestinal cancers to allow meta-analyses.
Conclusion
Bariatric surgery appears to reduce the risk of oesophageal, liver, and gallbladder cancers, supporting a role in both weight management and cancer prevention. Standardization in reporting surgical procedures is needed to clarify effects by bariatric surgery type.
Date Issued
2026-04-01
Date Acceptance
2025-12-22
Citation
BJS Open, 2026, 10 (2)
ISSN
2474-9842
Publisher
Oxford University Press
Journal / Book Title
BJS Open
Volume
10
Issue
2
Copyright Statement
© The Author(s) 2026. Published by Oxford University Press on behalf of BJS Foundation Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
10.1093/bjsopen/zrag006
Subjects
obesity
obesity-related
liver
gallbladder
oesophageal
systematic review
Publication Status
Published
Article Number
ARTN zrag006
Date Publish Online
2026-04-06