{"entity":{"id":"idea-nl-bariatric-cancer-registry-linkage","kind":"idea","name":"Link bariatric and GLP-1 registries to cancer registries in every country that has both","aka":[],"tldr":"Millions of people have had weight-loss surgery or now take weight-loss drugs. Linking those records to cancer registries would show, cancer by cancer, how much reversing obesity prevents, for almost no cost.","summary":"Nordic registries and the Cleveland Clinic SPLENDID cohort show about a third fewer obesity-related cancers after bariatric surgery, but individual sites (oesophageal adenocarcinoma, colorectal, pancreatic) are underpowered, and the emerging GLP-1 receptor agonist data are from insurance claims with short follow-up. Most high-income countries have national bariatric surgery registries, complete cancer registries and prescription databases; a federated linkage with a common protocol would produce site-specific, sex-specific estimates, detect any unexpected harm (post-bariatric colorectal cancer, thyroid), and provide the counterfactual against which GLP-1 drugs can be judged.","asOf":"2026-09-08","links":[{"label":"Bottleneck evidence (Weak real-world evidence and registries): Gyawali, Hey & Kesselheim, Assessment of the clinical benefit of cancer drugs receiving accelerated approval (JAMA Intern Med 2019)","url":"https://doi.org/10.1001/jamainternmed.2019.0462"}],"tags":[],"related":["idea-prev-glp1-cancer-prevention-rct"],"cancers":["endometrial","colorectal","esophageal","hcc","pancreatic","rcc"],"sections":["nutrition-lifestyle","prevention"],"technologies":["bariatric-surgery-cancer-incidence","glp1-agonists-cancer-risk"],"targets":[],"drugs":[],"companies":[],"institutions":["karolinska","cleveland-clinic"],"pathways":[],"terms":["obesity-related-cancers","real-world-evidence"],"trials":[],"people":[],"bottlenecks":["b-real-world-evidence","b-data-silos","b-prevention-adoption"],"keyPapers":["paper-gyawali-jama-intern-med"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"Federated linkage across at least five countries will show site-specific reductions in cancer incidence after bariatric surgery that scale with weight loss maintained at five years, and GLP-1 receptor agonist users will show a similar gradient by cumulative exposure.","rationale":"The exposure is common, the outcome registries exist, the analytic methods (target trial emulation) are mature, and randomised trials with cancer endpoints are a decade away. The data would inform both prevention policy and the design of any GLP-1 cancer trial.","test":"Common-protocol federated analysis (Sweden, Denmark, Finland, Scotland, Ontario, Israel) of bariatric surgery and GLP-1 receptor agonist exposure vs matched obese controls with cancer incidence by site as outcome; pre-registered, with results published within three years.","maturity":"early-clinical","actor":"data","cost":"small","horizonYears":3},"route":"/ideas/idea-nl-bariatric-cancer-registry-linkage/","neighbours":{"idea":[{"id":"idea-prev-glp1-cancer-prevention-rct","kind":"idea","name":"A trial of GLP-1 weight-loss drugs with cancer as the primary outcome","route":"/ideas/idea-prev-glp1-cancer-prevention-rct/"}],"cancer":[{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"endometrial","kind":"cancer","name":"Endometrial cancer","route":"/cancers/endometrial/"},{"id":"hcc","kind":"cancer","name":"Hepatocellular carcinoma","route":"/cancers/hcc/"},{"id":"esophageal","kind":"cancer","name":"Oesophageal cancer","route":"/cancers/esophageal/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"},{"id":"rcc","kind":"cancer","name":"Renal cell carcinoma","route":"/cancers/rcc/"}],"section":[{"id":"nutrition-lifestyle","kind":"section","name":"Diet, Exercise & Lifestyle","route":"/fronts/nutrition-lifestyle/"},{"id":"prevention","kind":"section","name":"Prevention & Risk","route":"/fronts/prevention/"}],"technology":[{"id":"bariatric-surgery-cancer-incidence","kind":"technology","name":"Bariatric surgery and cancer incidence","route":"/technologies/bariatric-surgery-cancer-incidence/"},{"id":"glp1-agonists-cancer-risk","kind":"technology","name":"GLP-1 receptor agonists and obesity-related cancer risk","route":"/technologies/glp1-agonists-cancer-risk/"}],"institution":[{"id":"cleveland-clinic","kind":"institution","name":"Cleveland Clinic Taussig Cancer Institute","route":"/institutions/cleveland-clinic/"},{"id":"karolinska","kind":"institution","name":"Karolinska University Hospital","route":"/institutions/karolinska/"}],"term":[{"id":"obesity-related-cancers","kind":"term","name":"Obesity-related cancers (IARC list of 13)","route":"/terms/obesity-related-cancers/"},{"id":"real-world-evidence","kind":"term","name":"Real-world evidence","route":"/terms/real-world-evidence/"}],"bottleneck":[{"id":"b-data-silos","kind":"bottleneck","name":"Data silos","route":"/bottlenecks/b-data-silos/"},{"id":"b-prevention-adoption","kind":"bottleneck","name":"Prevention we already have is not deployed","route":"/bottlenecks/b-prevention-adoption/"},{"id":"b-real-world-evidence","kind":"bottleneck","name":"Weak real-world evidence and registries","route":"/bottlenecks/b-real-world-evidence/"}],"paper":[{"id":"paper-gyawali-jama-intern-med","kind":"paper","name":"Assessment of the Clinical Benefit of Cancer Drugs Receiving Accelerated Approval","route":"/key-papers/paper-gyawali-jama-intern-med/"}]}}