Global obesity experts have proposed a large-scale, long-term follow-up study to verify whether the use of modern obesity treatments can significantly reduce cancer incidence. Obesity is known to trigger chronic inflammation and hormonal imbalances, creating a direct link to at least 13 types of cancer. These include colorectal, esophageal, liver, pancreatic, kidney, and postmenopausal breast cancer, among others.
New hope has emerged with the arrival of next-generation treatments: Novo Nordisk’s Wegovy (semaglutide) and Eli Lilly’s Mounjaro (tirzepatide). Wegovy mimics the appetite-regulating hormone glucagon-like peptide-1 (GLP-1), yielding an average weight loss of 15% over 68 weeks. Mounjaro targets both GLP-1 and GIP receptors, achieving weight loss of 20% to 22.5% over 72 weeks. Given that bariatric surgery—the gold standard for severe obesity—reduces weight by approximately 30% within two years, these drug therapies are reaching comparable levels of efficacy.
The Challenge of Long-Term Verification
Since last year, international organizations like the European Association for the Study of Obesity (EASO) have advocated for 10-year longitudinal studies to measure the reduction in obesity-related cancers. However, the primary obstacle is the immense time and financial burden. EASO estimates that to influence international treatment guidelines, a study would require at least 50,000 participants followed for a decade, incurring astronomical costs.
In response, a multinational panel of 21 obesity and cancer specialists has pivoted to a smaller preliminary study. This trial will involve 5,000 patients divided into control and experimental groups. Researchers will simulate cancer risk reduction over a six-month period to determine if a full-scale, long-term clinical trial is viable.
Anticipation for ECO2026
The results of this preliminary study, led by the University of Manchester, are scheduled for their first presentation at the European Congress on Obesity (ECO2026) in Istanbul this May. The outcome will dictate whether the medical community moves forward with a definitive, large-scale evaluation of these drugs' anti-cancer potential.
"We hope this will provide an opportunity to prevent hundreds of thousands of cancer cases worldwide," said Matthew Harris, PhD, of the University of Manchester, who leads the expert panel.
