Need for and design of a trial to test efficacy of weight loss interventions for cancer prevention: an international consensus using expert nominal group and Delphi methods.

The publication reports an international expert consensus exercise on whether and how to design a weight-loss intervention trial to prevent obesity-related cancers, in the context of rapidly expanding use of GLP-1 receptor agonists.

Using two nominal group meetings and three Delphi rounds with 54 multidisciplinary researchers, informed by patient input, the group iteratively developed and refined consensus statements. Retention across Delphi rounds was high (98%, 85%, 88%), and consensus was achieved on 25 statements.

Key points of agreement were:

• There is a clear need for prospective clinical trial evidence to guide obesity-related cancer prevention strategies, beyond existing observational data and bariatric surgery cohorts.
• Any such trial should focus on populations at high risk for obesity-related cancers, rather than the general population, to make it more feasible and informative.
• GLP-1 receptor agonists should be prioritized as the primary pharmacologic weight-loss intervention in these prevention trials, given their efficacy and current clinical impact.
• Future research should integrate mechanistic studies and evaluation of cancer precursors (e.g., biomarkers, premalignant lesions) to clarify how weight loss and GLP-1–based interventions influence carcinogenesis.

Overall, the consensus highlights both the scientific opportunity and the methodological complexity of conducting cancer prevention trials using modern weight-loss agents, and it calls for well-designed studies in high-risk groups with embedded mechanistic components.