Among 106,088 type 2 diabetes patients, GLP-1 receptor agonists were associated with 53% lower liver cancer and 77% lower pancreatic cancer risk compared to insulin, with no increased risk for 14 other cancer types.
77% lower pancreatic cancer riskGLP-1RA users showed dramatically lower pancreatic cancer incidence (HR 0.23) versus insulin users among 106,088 type 2 diabetes patients, along with 53% lower liver cancer risk
What the researchers found
Among 106,088 patients (53,924 GLP-1RA, remainder insulin), 1,594 (1.9%) developed cancer. GLP-1RA use was associated with significantly lower risk of liver cancer (HR: 0.47, 95% CI: 0.27-0.82) and pancreatic cancer (HR: 0.23, 95% CI: 0.11-0.51) compared to insulin. Risk of all 14 other cancer types was comparable between groups (all p>0.05), including thyroid cancer — a historical concern with GLP-1 drugs.
Why it matters
With tens of millions of people taking GLP-1 drugs, cancer safety is a paramount concern. This is one of the largest studies to comprehensively evaluate cancer risk across 16 tumor types. Not only does it provide reassurance (no increased risk for any cancer type), but the strong protective signals for liver and pancreatic cancer — two cancers closely linked to diabetes and obesity — suggest GLP-1 drugs may have anticancer properties through mechanisms like reduced inflammation, improved insulin sensitivity, and weight loss.
How the study worked
Retrospective cohort study using IBM MarketScan database (2013-2021). 106,088 patients with type 2 diabetes were categorized into GLP-1RA and insulin groups. Overlap Propensity Score Weighting controlled for confounders. Cox proportional hazards models assessed risk for 16 cancer types. Mean age 51 years, 51.3% male.
What this study cannot tell us
This is a retrospective observational study and cannot prove causation. The insulin comparison group may have more advanced diabetes, potentially confounding the results (protopathic bias). The follow-up period (2013-2021) may be too short for slow-growing cancers. Claims database data lacks clinical detail on cancer staging, BMI changes, and other confounders. Propensity score weighting reduces but cannot eliminate residual confounding. The impressive pancreatic cancer HR (0.23) should be interpreted cautiously given the small number of cases (n=87).
How to read the evidence
This is a large retrospective cohort study with propensity score weighting from a major claims database. While the sample size is impressive, the observational design cannot establish causation, and the insulin comparison group may introduce confounding. The protective effect sizes are large but should be confirmed in prospective studies.
When this study was published
Published in 2026, this is among the most comprehensive cancer safety analyses of GLP-1 receptor agonists, directly relevant to the ongoing evaluation of these blockbuster medications.
The bigger picture
The potential anticancer effects of GLP-1 receptor agonists represent one of the most exciting emerging areas in the field. Liver and pancreatic cancers are among the deadliest, with limited treatment options and strong ties to metabolic dysfunction. If GLP-1 drugs truly reduce these cancer risks — through weight loss, reduced liver fat, decreased inflammation, or direct GLP-1R-mediated effects on cancer cells — this could add an entirely new dimension to their therapeutic value. Combined with cardiovascular and kidney benefits, GLP-1 drugs may prove to be the most broadly beneficial drug class discovered in decades.
Questions still open
- Are the liver and pancreatic cancer risk reductions driven by weight loss, metabolic improvement, or direct GLP-1R effects on tumor cells?
- Would randomized trial data confirm these large protective effect sizes, or is residual confounding inflating them?
- Could GLP-1 drugs be studied as cancer chemopreventive agents in high-risk populations?
Common questions
Can GLP-1 drugs prevent cancer?
Should I worry about thyroid cancer with GLP-1 drugs?
Read the original research
Cancer Incidence Among Users of Glucagon-Like Peptide-1 Receptor Agonists.
Journal of general internal medicine
Citation
Rashid, Zayed; Woldesenbet, Selamawit; Khalil, Mujtaba; Altaf, Abdullah; Zindani, Shahzaib; Mevawalla, Areesh; Sarfraz, Azza; Mumtaz, Khalid; Pawlik, Timothy M. (2026). Cancer Incidence Among Users of Glucagon-Like Peptide-1 Receptor Agonists.. Journal of general internal medicine. https://doi.org/10.1007/s11606-026-10300-1